Journal articles: 'STS [Scanning tunneling spectroscopy]'

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Morita, Seizo, Yutaka Maita, and Yoshiaki Takahashi. "Scanning Tunneling Potentiometry/Spectroscopy (STP/STS)." Japanese Journal of Applied Physics 28, Part 2, No. 11 (November 20, 1989): L2034—L2036. http://dx.doi.org/10.1143/jjap.28.l2034.

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Kano, Shinya, Tsukasa Tada, and Yutaka Majima. "Nanoparticle characterization based on STM and STS." Chemical Society Reviews 44, no. 4 (2015): 970–87. http://dx.doi.org/10.1039/c4cs00204k.

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Alam, MS, FA Chowdhury, RW Saalfrank, AV Postnikov, and P. Müller. "STM Spectroscopy of Star-Type Molecular Magnet." Dhaka University Journal of Science 60, no. 1 (April 14, 2012): 87–91. http://dx.doi.org/10.3329/dujs.v60i1.10343.

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In order to achieve a better understanding of how scanning tunneling microscopy (STM) images of metallo-complexes are related to the geometric and electronic structure, we performed scanning microscopy (STM) and scanning tunneling spectroscopy (STS) techniques on [FeIIIFeIII 3L6] (L= N-methylaminediethanolate) star-type tetranuclear molecular magnet. The experiments were performed under ambient condition. We were able to image single molecule by STM with submolecular resolution. In our STS measurements we found a rather large signal at the positions of iron ion centers in the molecules. This direct addressing of metal centers was further confirmed by density functional theory (DFT) calculations.DOI: http://dx.doi.org/10.3329/dujs.v60i1.10343 Dhaka Univ. J. Sci. 60(1): 87-91 2012 (January)

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Hatch, John Byron, Luisa Whittaker-Brooks, Tai-Lung Wu, Gen Long, Hao Zeng, G. Sambandamurthy, Sarbajit Banerjee, and Hong Luo. "Intermediate metallic phase in VO2observed with scanning tunneling spectroscopy." Phys. Chem. Chem. Phys. 16, no. 27 (2014): 14183–88. http://dx.doi.org/10.1039/c4cp01551g.

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BOBBA, F., R. LAMY, D. RODITCHEV, W. SACKS, J. KLEIN, V. FERRANDO, C. FERDEGHINI, F. GIUBILEO, and A. M. CUCOLO. "SCANNING TUNNELING SPECTROCOPY ON MgB2 THIN FILMS." International Journal of Modern Physics B 17, no. 04n06 (March 10, 2003): 446–52. http://dx.doi.org/10.1142/s021797920301608x.

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Low temperature Scanning Tunneling Microscopy/Spectroscopy (STM/STS) was used to study the superconducting properties of as grown MgB2 thin films. Two different Pulsed Laser Ablation deposition procedures were used to fabricate the samples. Depending on growth conditions, STS/STM analysis revealed either superconducting or normal metallic behavior on the sample surfaces. In the first case the tunneling spectra with well-pronounced superconducting gap of 2.6-3.2 meV were observed at T = 4.2 K. STS spectra were found to be position independent, thus showing a very high spatial homogeneity of the films. No evidence of double gap structures was found. Moreover, in contrast with a bulk TC = 35.7K of the samples, the superconductivity with a damped TC was observed on the surface. In the second case, the superconducting features were completely absent in the tunneling spectra. We associate such a behaviour of the samples of second type with the presence of a thick metallic cap layer all over the surface.

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Carroll, D. L., P. M. Ajayan, and S. Curran. "Local Electronic Structure in Ordered Aggregates of Carbon Nanotubes: Scanning Tunneling Microscopy/scanning Tunneling Spectroscopy Study." Journal of Materials Research 13, no. 9 (September 1998): 2389–95. http://dx.doi.org/10.1557/jmr.1998.0332.

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The recent application of tunneling probes in electronic structure studies of carbon nanotubes has proven both powerful and challenging. Using scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS), local electronic properties in ordered aggregates of carbon nanotubes (multiwalled nanotubes and ropes of single walled nanotubes) have been probed. In this report, we present evidence for interlayer (concentric tube) interactions in multiwalled tubes and tube-tube interactions in singlewalled nanotube ropes. The spatially resolved, local electronic structure, as determined by the local density of electronic states, is shown to clearly reflect tube-tube interactions in both of these aggregate forms.

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Saad, Mahmoud M., Tamer Abdallah, Khalid Easawi, Sohair Negm, and Hassan Talaat. "Interfacial scanning tunneling spectroscopy (STS) of chalcogenide/metal hybrid nanostructure." Applied Surface Science 337 (May 2015): 1–5. http://dx.doi.org/10.1016/j.apsusc.2015.01.152.

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WINIARZ, SZYMON, PIOTR BISKUPSKI, STANISLAW SZUBA, SLAWOMIR MIELCAREK, and RYSZARD CZAJKA. "STS INVESTIGATIONS OF METALLIC NANOSTRUCTURES DEPOSITED ON Bi2Te3." Surface Review and Letters 14, no. 03 (June 2007): 357–60. http://dx.doi.org/10.1142/s0218625x07009657.

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Bi 2 Te 3 has attracted attention due to its potential applications in the microfabrication of integrated thermoelectric devices. It is also interesting to study the metallization process of this compound. Metallic nanostructures were deposited by means of an electron gun evaporator in ultra high vacuum (UHV) conditions (10-8 Pa) on the freshly cleaved 0001 surface of the crystal Bi 2 Te 3. Measurements were conducted using the commercially available Omicron UHV scanning tunneling microscope (STM). Scanning tunneling spectroscopy (STS) measurements were performed using current imaging tunneling spectroscopy (CITS), and subsequent calculation of the dI/dV maps. Metallic characteristics were observed on nickel islands since early stages of the growth. CITS and dI/dV maps showed distinct contrast between the substrate and metallic islands. Similar contrast was not observed in the case of titanium, most probably due to an intercalation process. Occurring of such a process was confirmed by the appearance of the superlattice structure.

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Chang, Sung Sik, and Akira Sakai. "Scanning Tunneling Microscopy Studies of Porous and Oxidized Zn." Key Engineering Materials 326-328 (December 2006): 373–76. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.373.

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This paper reports the scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) studies of porous Zn (p- Zn) prepared by electrochemical etching. Further, the post annealing of the p- Zn is carried out and STM/STS investigations are also performed. STM studies of these samples reveal the porous structure and display small, pseudo-spherical shaped crystals in the range of 2 and 100 nm, 2 and 50 nm, and similar average corrugation of 9 nm for p- Zn and oxidized p-Zn. STS analysis of freshly prepared p- Zn shows a band gap of 2.4 eV along with metallic conductance behavior. However, oxidized p- Zn reveals a distinct wide band gap (3 eV) and shows shallow donor states near the conduction band.

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Ting, Wu, R. Itti, Y. Ishimaru, G. Gu, Y. Enomoto, N. Koshizuka, and S. Tanaka. "Scanning tunneling microscope/scanning tunneling spectroscopy investigation of the structural modulation on the surface of cleaved Bi2Sr2CaCu2Oy, single crystal." Journal of Materials Research 10, no. 4 (April 1995): 817–22. http://dx.doi.org/10.1557/jmr.1995.0817.

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The surface of cleaved Bi2Sr2 CaCu2O3 (Bi2212) single crystals has been studied by means of scanning tunneling microscope (STM) and scanning tunneling spectroscopy (STS) at room temperature in ultrahigh vacuum. We obtain atomic images of the BiO surface using logarithmic current mode and conventional mode. It is demonstrated that the Bi atoms in the BiO plane are not missing. Some Bi atoms are depressed down below the BiO surface. STS obtained at different places of the surface shows more or less the same feature, indicating that local electronic density of states does not change much due to the depression or the well-known structural modulation. The possible origins of the variation in the period of the structural modulation in the BiO plane of cleaved Bi2212 single crystals extracted from STM images are also studied.

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WU, A. T., N. KOSHIZUKA, and S. TANAKA. "TUNNELING ASYMMETRY IN SUPERCONDUCTING Nd1Ba2Cu3Oy SINGLE CRYSTALS." Modern Physics Letters B 13, no. 21 (September 10, 1999): 735–42. http://dx.doi.org/10.1142/s0217984999000920.

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Clean, stable, and atomically flat (001) surfaces of the as-prepared Nd 1 Ba 2 Cu 3 O y (Nd123) single crystals have been investigated using a Low Temperature UltraHigh Vacuum Scanning Tunneling Microscope/Spectroscopy (STM/STS) system at 10 K. Several sets of highly reproducible STS data show the existence of an asymmetry in the tunneling spectra in superconducting Nd123 single crystals. The asymmetry is found to be intrinsic and can be explained by assuming that the pairing potential is a function of the kinetic energy of the charge carriers. The STS data are compared with the predictions of different theoretical models. The data on the (001) surfaces may be better fitted by assuming an S wave symmetry. Pure d(x2-y2) symmetry is ruled out.

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Hellenthal, Chris, Kai Sotthewes, Martin H. Siekman, E. Stefan Kooij, and Harold J. W. Zandvliet. "Closed-loop conductance scanning tunneling spectroscopy: demonstrating the equivalence to the open-loop alternative." Beilstein Journal of Nanotechnology 6 (May 6, 2015): 1116–24. http://dx.doi.org/10.3762/bjnano.6.113.

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We demonstrate the validity of using closed-loop z(V) conductance scanning tunneling spectroscopy (STS) measurements for the determination of the effective tunneling barrier by comparing them to more conventional open-loop I(z) measurements. Through the development of a numerical model, the individual contributions to the effective tunneling barrier present in these experiments, such as the work function and the presence of an image charge, are determined quantitatively. This opens up the possibility of determining tunneling barriers of both vacuum and molecular systems in an alternative and more detailed manner.

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Kuwabara, M., W. Lo, and J. C. H. Spence. "Observation of elastic strain by REM while tunneling from a contaminated surface." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 38–39. http://dx.doi.org/10.1017/s0424820100152161.

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To explain anomalously low work functions observed by Scanning Tunneling Spectroscopy (STS) a anomalously large corrugation heights observed by Scanning Tunneling Microscopy (STM) it has be suggested that the STM tip and an insulating adsorbate layer on the sample surface may be contact. STM contrast mechanisms for atomic resolution imaging of graphite and other layer compounds and for imaging uncoated DNA in a buffer solution have also been suggested based on t possibility that the tip and sample are in contact. Whether or not tip-sample contact occurs whitunneling is, clearly, an important question which has not been satisfactorily answered by STM/STS.

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Jahanbekam, Abdolreza, Colin Harthcock, and David Y. Lee. "Radical induced intermolecular linkage and energy level modifications of a porphyrin monolayer." Chemical Communications 53, no. 6 (2017): 1104–7. http://dx.doi.org/10.1039/c6cc09580a.

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A new method to directly modify the surface structure and energy levels of a porphyrin monolayer was examined with molecular-scale resolution using scanning tunneling microscopy and spectroscopy (STM and STS) and presented in this communication.

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KAWASAKI, TOYOSEI, TAKASHI ICHIMURA, HIROSHI KISHIMOTO, ADE ASNEIL AKBAR, TAKASHI OGAWA, and CHUHEI OSHIMA. "DOUBLE ATOMIC LAYERS OF GRAPHENE/MONOLAYER h-BN ON Ni(111) STUDIED BY SCANNING TUNNELING MICROSCOPY AND SCANNING TUNNELING SPECTROSCOPY." Surface Review and Letters 09, no. 03n04 (June 2002): 1459–64. http://dx.doi.org/10.1142/s0218625x02003883.

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Using STM, we have directly confirmed the incommensurate stacking of double atomic layers of graphene and monolayer h-BN on Ni(111). The formation of a graphene layer weakens the interfacial interaction between monolayer h-BN and Ni(111), resulting in insulating h-BN layers, while a pristine monolayer h-BN on Ni(111) is metallic. The STS spectra of the double atomic layers showed a tunneling character with a band gap of 0.5 eV.

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NISHIZAKI, TERUKAZU, TAKAHIKO SASAKI, NORIO KOBAYASHI, YOSHIHIKO TAKANO, MASANORI NAGAO, and HIROSHI KAWARADA. "SPATIAL VARIATION OF TUNNELING SPECTRA IN (111)-ORIENTED FILMS OF BORON-DOPED DIAMOND PROBED BY STM/STS." International Journal of Modern Physics B 27, no. 15 (June 4, 2013): 1362014. http://dx.doi.org/10.1142/s0217979213620142.

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We report on scanning tunneling microscopy/spectroscopy (STM/STS) experiments on boron-doped diamond films. The tunneling conductance dI/dV spectra measured on the (111)-oriented surface show spatial variations which distribute irrespective of the surface morphology. The spatial variations are discussed in terms of characteristic features of the superconductivity under the condition of the considerable disorder by the boron doping.

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Koslowski, Berndt, Anna Tschetschetkin, Norbert Maurer, Elena Mena-Osteritz, Peter Bäuerle, and Paul Ziemann. "Terthiophene on Au(111): A scanning tunneling microscopy and spectroscopy study." Beilstein Journal of Nanotechnology 2 (September 9, 2011): 561–68. http://dx.doi.org/10.3762/bjnano.2.60.

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Terthiophene (3T) molecules adsorbed on herringbone (HB) reconstructed Au(111) surfaces in the low coverage regime were investigated by means of low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) under ultra-high vacuum conditions. The 3T molecules adsorb preferentially in fcc regions of the HB reconstruction with their longer axis oriented perpendicular to the soliton walls of the HB and at maximum mutual separation. The latter observation points to a repulsive interaction between molecules probably due to parallel electrical dipoles formed during adsorption. Constant-separation (I-V) and constant-current (z-V) STS clearly reveal the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals, which are found at −1.2 eV and +2.3 eV, respectively. The HOMO–LUMO gap corresponds to that of a free molecule, indicating a rather weak interaction between 3T and Au(111). According to conductivity maps, the HOMO and LUMO are inhomogeneously distributed over the adsorbed 3T, with the HOMO being located at the ends of the linear molecule, and the LUMO symmetrically with respect to the longer axis of the molecule at the center of its flanks. Analysis of spectroscopic data reveals details of the contrast mechanism of 3T/Au(111) in STM. For that, the Shockley-like surface state of Au(111) plays an essential role and appears shifted outwards from the surface in the presence of the molecule. As a consequence, the molecule can be imaged even at a tunneling bias within its HOMO–LUMO gap. A more quantitative analysis of this detail resolves a previous discrepancy between the fairly small apparent STM height of 3T molecules (1.4–2.0 nm, depending on tunneling bias) and a corresponding larger value of 3.5 nm based on X-ray standing wave analysis. An additionally observed linear decrease of the differential tunneling barrier at positive bias when determined on top of a 3T molecule is compared to the bias independent barrier obtained on bare Au(111) surfaces. This striking difference of the barrier behavior with and without adsorbed molecules is interpreted as indicating an adsorption-induced dimensionality transition of the involved tunneling processes.

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UCHIYAMA, TOSHIHIRO. "THE ATOMIC AND ELECTRONIC STRUCTURE OF THE SINGLE STEPS ON THE Si(001) SURFACE." Modern Physics Letters B 07, no. 09 (April 20, 1993): 591–99. http://dx.doi.org/10.1142/s0217984993000576.

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Recent development of the scanning tunneling microscope (STM), which is one of the most powerful tools to study solid surface, has given the atomic-resolution images of the terraces and steps on the Si(001) vicinal surface. Around the S A step, the spectrum of the scanning tunneling spectroscopy (STS) exhibits a few characteristic peaks. This observation suggests that there exists an unique state at the step edge. In this review, I describe the atomic and electronic structure of the single steps on the Si(001) surface.

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Gao, Yang, and Kai-He Ding. "Scanning tunneling spectroscopy of a magnetic adatom on graphene." International Journal of Modern Physics B 28, no. 31 (December 8, 2014): 1450225. http://dx.doi.org/10.1142/s0217979214502257.

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We present a theoretic study on scanning tunneling spectroscopy (STS) of a magnetic adatom on graphene. Three typical configurations of adatoms on graphene are considered explicitly: the adatom is on the top of a carbon atom (TC), in a substitutional site (SC), or above the center of the honeycomb hexagon (HC). Based on the nonequilibrium Green's function method, we derive the local density of state (LDOS) for the adatom and the differential conductance through the scanning tunneling microscopy (STM) device. Our results show that in comparison with the cases of the TC and SC, there exists an anomalous broadening of the local adatom energy level in the HC, which pushes the adatom energy to first cross the Fermi level, leading to the appearance of an antiresonance in the LDOS due to the interference between the Kondo resonance and the broadened adatom level. Correspondingly, the bias dependence of the differential conductance in the HC exhibits a more asymmetric sharp Kondo peak pinned to the gate voltage, and its height still remains significantly large compared to that for the other two cases. Additionally, with decreasing the gate voltage, the Kondo peak in the differential conductance gradually decays, and eventually vanishes in the absence of the gate voltage.

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Bonnell, Dawn A., and Qian Zhong. "Local geometric and electronic structure of oxides using scanning tunneling microscopy/spectroscopy." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1480–81. http://dx.doi.org/10.1017/s0424820100132030.

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The potential of scanning tunneling microscopy (STM) and related scanning probe microscopies is amply demonstrated by the geometric increase in the number of papers utilizing the techniques that are published each year. The power of STM derives, not only from imaging capabilities, but also from associated spectroscopies which can provide local information about the density of states and work function. Although the technique has been applied to a wide range of metal and semiconductor surfaces, application to large bandgap materials such as oxides is difficult. We demonstrate the successful application of STM/STS to oxides with an analysis of the effect of reduction mechanism on the geometric and electronic structure of TiO2 (110). The structure of defects in oxides is critical in that it affects many properties of practical interest including catalysis, photoelectrolysis, and electron transport. The presence of defects can affect the local cation valence, such that the variation of d-orbital occupation results in a range of electronic properties, from insulating to semiconducting in nature. STM/STS is the ideal tool to probe the structure of these defects.

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Lee, Nam-Suk, Chang-Heon Yang, Won-Suk Choi, and Young-Soo Kwon. "Scanning Tunneling Microscopy Imaging and Spectroscopy of a Single Viologen Molecule." Journal of Nanoscience and Nanotechnology 8, no. 9 (September 1, 2008): 4621–25. http://dx.doi.org/10.1166/jnn.2008.ic37.

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A low-temperature ultrahigh-vacuum scanning tunneling microscope (UHV-STM) was used to image viologen (N-methyl-N′-di (8-mercaptooctyl)-4,4′-bipyridinium; HSC8VC8SH) molecules and to perform local spectroscopic measurements on these molecules. Self-assembly of viologen molecules was conducted on Au (111), which had been thermally deposited onto freshly cleaved, heated mica. Here, we demonstrate a novel SAM matrix appropriate for the isolation of viologen molecules composed of octanethiol (C8) in which HSC8VC8SH was inserted at defects in the molecular lattice. The isolated single molecules of viologen inserted in the SAM matrix were observed as protrusions in STM topography using a constant current mode. STM images at 298 K showed protrusions with a topographic height of about 2.71 nm (HSC8VC8SH) with viologen molecules that self-assembled on the substrate. The current–voltage (I–V) characteristics were measured while the electrical properties of the formed monolayer were scanned using scanning tunneling spectroscopy (STS). We found the high peak current-like rectification at +1.14 V (HSC8VC8SH). The rectification ratios, RR = J (at +2.5 V)/J (at −2.5 V), are in the range of 4.47.

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González-Carrazco, A., M. Herrera-Zaldívar, and U. Pal. "Studies of Point Defect Formation and Self-Compensation in Indium Doped ZnO Nanorods by STM and STS." Journal of Nanoscience and Nanotechnology 8, no. 12 (December 1, 2008): 6598–602. http://dx.doi.org/10.1166/jnn.2008.18432.

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The effect of indium doping on the point defect formation in ZnO nanostructures is studied by scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) techniques. While the incorporation of a donor dopant like indium should increase the n-type conductivity of ZnO nanostructures, it has been found that formation of VZn native acceptors in heavily doped ZnO nanostructures produces self-compensation effect, creating acceptor states in their band gap. Presence of both donor and acceptor states in heavily indium doped ZnO nanostructures are probed and identified. The mechanism of formation of such donor and acceptor states is discussed.

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Dey, Shirshendu, Sushama Pethkar, Suguna D. Adyanthaya, Murali Sastry, and C. V. Dharmadhikari. "New approach towards imaging λ-DNA using scanning tunneling microscopy/spectroscopy (STM/STS)." Bulletin of Materials Science 31, no. 3 (June 2008): 309–12. http://dx.doi.org/10.1007/s12034-008-0049-6.

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LUO, YUAN, LAN LUO, KAI SUN, MIN-LONG TAO, and JUN-ZHONG WANG. "STM STUDY OF THE ADSORPTION OF SINGLE-MOLECULE MAGNET Fe4 ON Bi(111) SURFACE." Surface Review and Letters 22, no. 05 (August 27, 2015): 1550060. http://dx.doi.org/10.1142/s0218625x15500602.

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Single-molecule magnets (SMMs) have unique magnetic properties such as quantum tunneling of magnetization and quantum coherent oscillation, which have potential applications in quantum computation and information storage. In this paper, using the tip-deposition method, we have grafted individual Fe 4 molecules onto the semi-metallic Bi (111) surface. Low temperature scanning tunneling microscope (LT-STM) was used to characterize the molecular morphology and electronic structures. It was found that individual Fe 4 molecules reveal a triangle shape, which is consistent with the molecular structure of Fe 4. Scanning tunneling spectroscopy (STS) analysis indicated that the HOMO–LUMO gap is 0.49 eV. These studies provide direct information about the adsorption of individual SMMs on semi-metal surfaces.

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Hou, J. G., and Kedong Wang. "Study of single molecules and their assemblies by scanning tunneling microscopy." Pure and Applied Chemistry 78, no. 5 (January 1, 2006): 905–33. http://dx.doi.org/10.1351/pac200678050905.

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The recent rapid advances in nanotechnology, especially those based on molecules, are due in large part to our newly acquired abilities to measure and manipulate individual molecules and their assemblies. Among all the approaches for the study of single molecules, scanning tunneling microscopy (STM) is unique and powerful owing to its ability to accurately probe and control single molecules. High-resolution spatial imaging combined with scanning tunneling spectroscopy (STS) helps scientists investigate and resolve many chemical and physical problems at the molecular level. In this paper, we review our recent studies of single molecules and their assemblies by combining STM experiments and theoretical simulations based on the density functional theory (DFT).

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ZAVODINSKY, V. G., and I. A. KUYANOV. "INFLUENCE OF A TIP/SAMPLE INTERACTION ON SCANNING TUNNELING SPECTROSCOPY DATA." Surface Review and Letters 02, no. 02 (April 1995): 219–23. http://dx.doi.org/10.1142/s0218625x95000248.

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The electronic states and the tunnel current for the W/Si and W/Al tip/sample systems were calculated by the first-principles discrete-variational method of the local-density approximation. It was found that the local-electronic structure of the Si surface resembles that of a free sample even for the tip/sample distances of 2–3 Å. The electronic structure of the Al surface is more sensitive to the tip/sample interaction and approaches the free surface form when the tip/sample distance is larger than 4 Å. The local density of states of the W tip also depends on the tip/sample distance and must be taken into account in the tunnel-current calculations and in the interpretations of the STS data.

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YAMADA, Toyokazu, and Tadashi MIZOGUCHI. "Spin-polarized Scanning Tunneling Microscopy/Spectroscopy and Quantitative Analysis Studied on Mn(001)." Hyomen Kagaku 26, no. 1 (2005): 2–10. http://dx.doi.org/10.1380/jsssj.26.2.

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Choi, Jeong-Woo, Doo-Bong Lee, Byung-Keun Oh, Junhong Min, and Kun Soo Kim. "Molecular Scale Photodiode Composed of Recombinant Ferredoxin/Chlorophyll a Heterostructure." Journal of Nanoscience and Nanotechnology 8, no. 9 (September 1, 2008): 4527–32. http://dx.doi.org/10.1166/jnn.2008.ic23.

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Photoelectrical rectifying property of biomolecular heterostructures is investigated in molecular scale. Recombinant ferredoxin and chlorophyll a were used as an electron acceptor and a sensitizer respectively in the molecular layer by mimicking photosynthesis. A self-assembled monolayer of recombinant ferredoxin was formed on Au surface, and then chlorophyll a was deposited onto the recombinant ferredoxin layer by Langmuir-Blodgett method. The formation of recombinant ferredoxin/chlorophyll a hetero-layers was confirmed by the SPR (surface plasmon resonance) spectroscopy, and the surface was observed by the STM (scanning tunneling microscopy). The rectifying property by the STS (scanning-tunneling-spectroscopy) based current–voltage characteristics was achieved in the recombinant ferredoxin/chlorophyll a hetero-layers. Thus, proposed hetero-layers functioned as a rectifier that can be useful property for the development of molecular-scale bioelectronic devices.

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PEREG-BARNEA, T., and M. FRANZ. "QUASIPARTICLE INTERFERENCE PATTERNS AS A TEST FOR THE NATURE OF THE PSEUDOGAP PHASE IN THE CUPRATE SUPERCONDUCTORS." International Journal of Modern Physics B 19, no. 04 (February 10, 2005): 731–61. http://dx.doi.org/10.1142/s0217979205026658.

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Electrons, when scattered by static random disorder, form standing waves that can be imaged using scanning tunneling microscopy. Such interference patterns, observable by the recently developed technique of Fourier transform scanning tunneling spectroscopy (FT-STS), are shown to carry unique fingerprints characteristic of the electronic order present in a material. We exploit this feature of the FT-STS technique to propose a test for the nature of the enigmatic pseudogap phase in the high-Tc cuprate superconductors. Through their sensitivity to the quasiparticle spectra and coherence factors, the FT-STS patterns, in principle, carry enough information to unambiguously determine the nature of the condensate responsible for the pseudogap phenomenon. In practice, the absence of a detailed understanding of the scattering mechanism, together with the experimental uncertainties, prevent such an unambiguous determination. We argue, however, that the next generation of FT-STS experiments, currently underway, should be able to distinguish between the pseudogap dominated by the remnants of superconducting order from the pseudogap dominated by some competing order in the particle-hole channel. Using general arguments and detailed numerical calculations, we point to certain fundamental differences between the two scenarios and discuss the prospects for future experiments.

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Kawai, Tomoji, and Masaki Kanai. "Superconductivity and scanning tunneling microscopy (STM) / spectroscopy (STS) of transition metal oxide artificial lattices." Journal of Low Temperature Physics 105, no. 5-6 (December 1996): 1349–58. http://dx.doi.org/10.1007/bf00753888.

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LEE, NAM-SUK, HOON-KYU SHIN, and YOUNG-SOO KWON. "CURRENT–VOLTAGE PROPERTIES OF SELF-ASSEMBLY MONOLAYERS ON AU(111) SUBSTRATE USING SCANNING TUNNELING MICROSCOPY." International Journal of Nanoscience 05, no. 06 (December 2006): 907–11. http://dx.doi.org/10.1142/s0219581x06005352.

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This study observes the morphology of self-assembled organic thin film that is formed at room temperature using a Scanning Tunneling Microscopy (STM) and examines its electrical properties using a Scanning Tunneling Spectroscopy (STS). The specimen used in this experiment that has a functional group for both sides and will be controlled to make self-assembled onto the Au (111) substrate. After the dilution of the specimen by 1 mM/ml and self-assembled onto the Au (111) substrate. Using a STM, the images of organic thin film can be observed. In addition, the electrical properties of organic thin film can also be examined by the junction structure of STM–organic thin film– Au (111) substrate by using a STM tip. As a result, we measured current–voltage (I–V) curve using STS, I–V curve also clearly shows several current peaks between the negative bias region (-1.42 V) and the positive bias region (1.30 V), respectively.

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König, Thomas, Georg H. Simon, Lars Heinke, Leonid Lichtenstein, and Markus Heyde. "Defects in oxide surfaces studied by atomic force and scanning tunneling microscopy." Beilstein Journal of Nanotechnology 2 (January 3, 2011): 1–14. http://dx.doi.org/10.3762/bjnano.2.1.

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Surfaces of thin oxide ﬁlms were investigated by means of a dual mode NC-AFM/STM. Apart from imaging the surface termination by NC-AFM with atomic resolution, point defects in magnesium oxide on Ag(001) and line defects in aluminum oxide on NiAl(110), respectively, were thoroughly studied. The contact potential was determined by Kelvin probe force microscopy (KPFM) and the electronic structure by scanning tunneling spectroscopy (STS). On magnesium oxide, different color centers, i.e., F0, F+, F2+ and divacancies, have different effects on the contact potential. These differences enabled classiﬁcation and unambiguous differentiation by KPFM. True atomic resolution shows the topography at line defects in aluminum oxide. At these domain boundaries, STS and KPFM verify F2+-like centers, which have been predicted by density functional theory calculations. Thus, by determining the contact potential and the electronic structure with a spatial resolution in the nanometer range, NC-AFM and STM can be successfully applied on thin oxide ﬁlms beyond imaging the topography of the surface atoms.

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Kondo, Y., K. Yagi, K. Kobayashi, H. Kobayashi, and Y. Yanaka. "Construction Of UHV-REM-PEEM for Surface Studies." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 1 (August 12, 1990): 350–51. http://dx.doi.org/10.1017/s0424820100180501.

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Recent development of ultra-high vacuum electron microscopy (UHV-EM) is very rapid. This is due to the fact that it can be applied to variety of surface science fields.There are various types of surface imaging in UHV condition; low energy electron microscopy (LEEM) [1], transmission (TEM) and reflection electron microscopy (REM) [2] using conventional transmission electron microscopes (CTEM) (including scanning TEM and REM)), scanning electron microscopy, photoemission electron microscopy (PEEM) [3] and scanning tunneling microscopy (STM including related techniques such as scanning tunneling spectroscopy (STS), atom force microscopy and magnetic force microscopy)[4]. These methods can be classified roughly into two; in one group image contrast is mainly determined by surface atomic structure and in the other it is determined by surface electronic structure. Information obtained by two groups of surface microscopy is complementary with each other. A combination of the two methods may give images of surface crystallography and surface electronic structure. STM-STS[4] and LEEM-PEEM [3] so far developed are typical examples.In the present work a combination of REM(TEM) and PEEM (Fig. 1) was planned with use of a UHV CTEM. Several new designs were made for the new microscope.

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LI, WEN-JUAN, YU-JIE SUN, TONG ZHANG, XIE-GANG ZHU, GUANG WANG, JIN-FENG JIA, XUCUN MA, XI CHEN, and QI-KUN XUE. "ENHANCEMENT OF SUPERCONDUCTIVITY OF Pb ULTRA-THIN FILMS BY THE INTERFACE EFFECT." Surface Review and Letters 17, no. 04 (August 2010): 437–40. http://dx.doi.org/10.1142/s0218625x10014235.

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We have studied the superconductivity of Pb ultra-thin films with thickness from 1 monolayer (ML) to 7 ML grown on Si(111) by molecular beam epitaxy. In situ low temperature scanning tunneling spectroscopy (STS) and angle-resolved photoemission spectroscopy (ARPES) measurements were performed on the films. It is suggested that the interface effect plays a critical role in enhancing the electron-phonon coupling, which consequently increases the superconducting transition temperature when a film reaches to the two-dimensional limit.

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MAFFEÏS, T. G. G., G. T. OWEN, S. P. WILKS, C. MALAGÙ, G. MARTINELLI, M. K. KENNEDY, and F. E. KRUIS. "ROOM TEMPERATURE AND ELEVATED TEMPERATURE CHARACTERIZATION OF NANOCRYSTALLINE SnO2 SURFACES BY SCANNING TUNNELING MICROSCOPY AND SPECTROSCOPY." International Journal of Nanoscience 03, no. 04n05 (August 2004): 519–24. http://dx.doi.org/10.1142/s0219581x04002322.

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Semiconductor gas sensors based on nanocrystalline SnO 2 offer many advantages over current technologies for detecting reducing gases, such as low cost, long lifetime, and high selectivity and sensitivity. However, the local surface properties on the nanoscale of SnO 2 nanocrystals are not fully understood, which impedes the exploitation of the full potential of SnO 2 for gas sensing applications. In this paper, we present a scanning tunneling microscopy and spectroscopy (STM/STS) study of nanocrystalline SnO 2 at room temperature, and under standard sensing conditions at 120°C. STS data indicate that the electronic surface properties change with nanoparticle size, temperature and exposure to gas. The surface density of states in the band gap is shown to increase with temperature while CO exposures induce a large drop in the density of band gap states as the CO molecules react with chemisorbed oxygen species.

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YOSHINOBU, J., H. UMEYAMA, M. NAGAO, K. OGUCHI, K. MUKAI, and Y. YAMASHITA. "CYCLOADDITION REACTION BETWEEN ORGANIC MOLECULES AND Si(100) AND ELECTRONIC PROPERTIES OF ADSORBED MOLECULES." International Journal of Nanoscience 06, no. 02 (April 2007): 95–102. http://dx.doi.org/10.1142/s0219581x0700433x.

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The mechanism of cycloaddition reaction between ethylene and the Si dimer on Si (100) is discussed from our recent experimental results using high-resolution electron energy loss spectroscopy and valence photoelectron spectroscopy at ~50 K. The weakly adsorbed π-complex state is identified as a precursor for di-σ bond formation and the activation barrier is roughly estimated to be ~0.2 eV. A different reaction route may exist since a di-σ species is also observed at low temperature. Using cycloaddition reaction, unsaturated organic molecules are chemically attached to the dimer on Si (100), and the adsorbed species are relatively stable. Thus, scanning tunneling spectroscopy (STS) measurements of a single adsorbed molecule can be carried out at room temperature. We report the STS results of 2-butyne adsorbed on Si (100).

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LI NAN, QIAN SHEND-FA, FU CHUN-SHENG, and XIE SI-SHEN. "A STUDY ON THE LOCAL ELECTRONIC STRUCTURE OF GRAPHITE SURFACE WITH SCANNING TUNNELING SPECTROSCOPY (STS)." Acta Physica Sinica 43, no. 2 (1994): 274. http://dx.doi.org/10.7498/aps.43.274.

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38

Rabia, Andi, Francesco Tumino, Alberto Milani, Valeria Russo, Andrea Li Bassi, Simona Achilli, Guido Fratesi, et al. "Scanning tunneling microscopy and Raman spectroscopy of polymeric sp–sp2 carbon atomic wires synthesized on the Au(111) surface." Nanoscale 11, no. 39 (2019): 18191–200. http://dx.doi.org/10.1039/c9nr06552k.

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SHIGETA, YUKICHI, RYOTA NEGISHI, and MASAHIKO SUZUKI. "LOCAL ELECTRONIC STATES ON TWO-DIMENSIONAL NANOSCALE ISLAND OF Si AND Ge FABRICATED ON Si(111) 7 × 7 SUBSTRATE." International Journal of Nanoscience 08, no. 06 (December 2009): 595–603. http://dx.doi.org/10.1142/s0219581x09006444.

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Nanoscale islands on semiconductor are a strong candidate as building block in nanodevices. In the nanoisland, some local deformation is induced by the surface tension, which has a great influence on the electronic property of the nanoislands. To study the electronic structure of two-dimensional (2D) nanoislands of Si and Ge on the Si(111) 7 × 7 surface, we formed nanoislands of the same size and measured with angle resolved ultraviolet photoelectron spectroscopy (ARUPS), scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS). We found that the nanoisland shows a characteristic fine structure due to some strain. We also calculated a relation between the strain and electronic state based on the density-functional theory. In the calculation, the dangling-bond state at the strained adatom on the nanoisland (SR state) shifts to lower energy, which has liner dependence with the height of the adatoms. The ARUPS spectrum and the STS show characteristic peaks corresponding to the SR state, whose energy depends on the deformation of the adatom. The height of the adatom on the nanoisland estimated from the energy difference is consistent with a result of the STM measurement. The strain of adatoms can be estimated from the electronic structure.

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40

Bonnell, D., Y. Liang, and D. Carroll. "Using STM to characterize interactions at metal-ceramic interfaces." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 1062–63. http://dx.doi.org/10.1017/s0424820100173042.

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The atomic interactions at metal/ceramic interfaces are often the limiting factor in mechanical and electrical properties. As such, much attention has been devoted to the issue. Experimental approaches include high resolution transmission electron microscopy, Auger electron spectroscopy, low energy electron diffraction, photoemission, etc. Scanning probe microscopies have yielded considerable insight into similar studies concerning semiconductors. Here we demonstrate how the spatial localization of scanning tunneling microscopy (STM) and tunneling spectroscopy (STS) can be exploited to elucidate atomic interactions at initial stages of metal/ceramic interface formation.A SrTiO3 single crystal is doped with 0.1% niobium so that the oxide will be conductive even when fully oxidized. The (001) surface was prepared with standard polishing techniques, then annealed at 1000 C in a UVH chamber backfilled with oxygen. This treatment results in a surface that consists of terraces 50-100 nm wide and several 100 nm long. The steps separating the terraces are 0.4 - 0.8 nm, i.e. one or two unit cells in height.

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Wiesendanger, R. "Correlation Between Nanoscale Structural, Electronic, and Magnetic Properties of Thin Films by Scanning-Probe Microscopy and Spectroscopy." MRS Bulletin 22, no. 8 (August 1997): 31–35. http://dx.doi.org/10.1557/s0883769400033789.

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Heteroepitaxial pseudomorphic thin-film growth allows the stabilization of solids in structures—that is, with crystalline symmetries and lattice constants that are far from those of the corresponding bulk material. This facilitates the tailoring of materials properties that do not exist in nature. Usually a strong correlation is found between the atomic, electronic, and magnetic structure of thin films, which leads to a drastic dependence of their physical properties on the details of growth conditions such as substrate temperature, evaporation rate, and background pressure. To learn more about the fundamental relationship between structural, electronic, and magnetic properties of thin films as well as to improve the reproducibility of their physical properties in view of technical applications, it is mandatory to apply experimental techniques with sufficient, ultimately atomic spatial resolution combined with high sensitivity. The class of scanning-probe microscopies and spectroscopies is ideally suited for that purpose as schematically illustrated in Figure 1. Scanning tunneling spectroscopy (STS) establishes the correlation between atomic structure and local electronic properties, while spin-polarized scanning tunneling spectroscopy (SPSTS) relates local electronic and magnetic properties. Additionally the correlationbetween topographical and magnetic structure can be addressed by magnetic force microscopy (MFM) though the spatial resolution is limited to about 10–50 nm. Since magnetic thin films are usually sensitive to oxidation, their preparation and characterization have to be performed in situ under ultrahigh vacuum (UHV) conditions in order to achieve reproducible experimental conditions. While STS is now routinely applied in UHV, it has only been recently that the first MFM studies under UHV conditions have been reported. In the following, representative examples of the application of STS, SPSTS, and MFM in ultrathin Fe, Gd, and Co films will be presented.

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Goodwin, Christopher M., Zachary E. Voras, Xiao Tong, and Thomas P. Beebe. "Soft Ion Sputtering of PAni Studied by XPS, AFM, TOF-SIMS, and STS." Coatings 10, no. 10 (October 12, 2020): 967. http://dx.doi.org/10.3390/coatings10100967.

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Herein is a study of the soft sputtering method, gas cluster ion sputtering (GCIS), and its effects on the atomic, morphologic, and band structure properties of polyaniline (PAni) as studied with X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry, atomic force microscopy, and scanning tunneling spectroscopy (STS). The GCIS source used was a 1000 argon atom cluster with 4 keV energy, which resulted in a sputter yield of 3.4 ± 0.2 × 10−3 nm3 per argon atom. Soft ion sputtering reduced the sample by explicitly removing the oxidized contaminants as determined by surface sensitive techniques: XPS and Time-of-flight secondary ion mass spectrometry (TOF-SIMS). By the use of STS we found that by removing the oxidized components, an overall shift of electronic states occurred, transitioning the states closer to the Fermi edge by 0.3 V.

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WANG, Y. F., X. H. YANG, S. F. WANG, H. Z. XIN, and A. P. LIU. "STUDY OF CONDUCTION MECHANISM AND SCANNING TUNNELING SPECTRUM OF NANO-CaCO3." International Journal of Modern Physics B 19, no. 01n03 (January 30, 2005): 663–65. http://dx.doi.org/10.1142/s0217979205029274.

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We have experimentally found out that an obvious tunnel current begins to appear between nano- CaCO 3 film and tip of STM when the bias voltage reaches 0.6V, above which there is a non-linear rise quickly. We further measure the scanning tunneling spectrum (STS) of nano- CaCO 3 and analyze it compared to that of Au and Silicon. The results show that CaCO 3, an insulating material, after nanometer processing presents a characteristic similarly to a metal, and the constraint to electrons is even smaller than a semiconductor. STS has not only well explained the spectroscopic mechanism of conducting performances of nano- CaCO 3, but also expanded applications of STM to one of the most important research areas. Moreover, the method can be applied to the study of the structure of superconductive materials and energy spectrum characterization.

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Fitzgerald, A. G., Y. Fan, P. John, C. E. Troupe, and J. I. B. Wilson. "The Surface Morphology and Characterisation of Electronic Properties of Boron Implanted Microwave Plasma CVD Diamond Films by Atomic Force and Scanning Tunneling Microscopies." Microscopy and Microanalysis 4, S2 (July 1998): 332–33. http://dx.doi.org/10.1017/s1431927600021784.

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The surface morphology and electronic properties of a low energy boron implanted diamond films with shallow doping, prepared by microwave plasma enhanced chemical vapour deposition (CVD), have been characterised by atomic force microscopy (AFM), scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) techniques.Both AFM and STM images taken at different locations on the films have exhibited similar morphological features on the (100) crystal surfaces. The crystal surfaces are not atomically flat but are composed of many hillocks as shown in Fig 1(a) to 1(c). The majority of values measured from the peaks of hillocks to the valleys are in the range of 2 to 5 nm, and the diameter of these hillocks is in the range of 50 to 250 nanometers. These crystal surface morphological features are believed to be caused in the high energy boron ion implantation process.

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Khatun, Salma, and Amlan J. Pal. "Dirac States of 2D Topological Insulators: Effect of Heterovalent Dopant-Content." Microscopy and Microanalysis 25, no. 6 (April 12, 2019): 1437–41. http://dx.doi.org/10.1017/s143192761900045x.

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AbstractWe have studied Bi2Se3 at its 2D-limit using scanning tunneling spectroscopy (STS). Bulk Bi2Se3 is a well-known topological insulator having gapless surface states. In the 2D limit, the interior of the material exhibits a band gap, whereas the periphery shows a gapless metallic state having a Dirac point. We demonstrate a method to tune the Fermi energy and hence the Dirac point of Bi2Se3 nanoplates through doping at the anionic site. For this purpose, STS measurements were carried out on the Bi2Se3 system. We have used bromide as a dopant, which turns the material to n-type in nature. As a result, STS studies infer that the Fermi energy (EF) shifted toward the conduction band and consequently the Dirac point could be found to move away from Fermi energy. Through STS measurements, we have demonstrated a correlation between the shift of Dirac point position and the dopant content. The size, shape, and compositions of Bi2Se3 nanoflakes and concentration of bromine in the doped nanostructures were determined using transmission electron microscopy, associated energy dispersive X-ray spectroscopy analysis, and X-ray diffraction.

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46

Bonnell, Dawn A., and Yong Liang. "The Nature of Oxide Surfaces: Topographic and Electronic Structure." Proceedings, annual meeting, Electron Microscopy Society of America 51 (August 1, 1993): 966–67. http://dx.doi.org/10.1017/s0424820100150666.

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Recent progress in the application of scanning tunneling microscopy (STM) and tunneling spectroscopy (STS) to oxide surfaces has allowed issues of image formation mechanism and spatial resolution limitations to be addressed. As the STM analyses of oxide surfaces continues, it is becoming clear that the geometric and electronic structures of these surfaces are intrinsically complex. Since STM requires conductivity, the oxides in question are transition metal oxides that accommodate aliovalent dopants or nonstoichiometry to produce mobile carriers. To date, considerable effort has been directed toward probing the structures and reactivities of ZnO polar and nonpolar surfaces, TiO2 (110) and (001) surfaces and the SrTiO3 (001) surface, with a view towards integrating these results with the vast amount of previous surface analysis (LEED and photoemission) to build a more complete understanding of these surfaces. However, the spatial localization of the STM/STS provides a level of detail that leads to conclusions somewhat different from those made earlier.

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Netzer, F. P., L. Vitali, J. Kraft, and M. G. Ramesy. "Surface Structures of Phosphorus and Indium on Si(111)." Surface Review and Letters 05, no. 01 (February 1998): 69–76. http://dx.doi.org/10.1142/s0218625x98000153.

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The interaction of vapor phase P2 with the [Formula: see text] monolayer surface at room temperature and elevated temperature has been monitored by scanning tunneling microscopy (STM) and spectroscopy (STS) in conjunction with Auger electron spectroscopy and low-energy electron diffraction (LEED). The surface rection can be readily followed by STM because of the very different contrast of the reacted areas in the STM images. The reaction develops around overlayer defects at room temperature and appears to be diffusion-limited, whereas at 300°C the reaction is initiated at the step edges, from which the reaction front progresses onto the lower terrace areas. At elevated temperature several ordered surface reconstructions, showing different STS fingerprints, are detected on the P–In/Si(111) surfaces, which are associated tentatively with P- and Si-terminated structures and an ordered InP phase.

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Caballero-Quintana, Irving, Daniel Romero-Borja, José-Luis Maldonado, Juan Nicasio-Collazo, Olivia Amargós-Reyes, and Antonio Jiménez-González. "Interfacial Energetic Level Mapping and Nano-Ordering of Small Molecule/Fullerene Organic Solar Cells by Scanning Tunneling Microscopy and Spectroscopy." Nanomaterials 10, no. 3 (February 28, 2020): 427. http://dx.doi.org/10.3390/nano10030427.

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Using scanning tunneling microscopy (STM) and spectroscopy (STS) at the liquid/solid interface, morphology evolution process and energetic level alignment of very thin solid films (thickness: <700 pm), of the low molecular weight molecule DRCN5T and DRCN5T:[70]PCBM blend are analyzed after applying thermal annealing at different temperatures. These films exhibit a worm-like pattern without thermal annealing (amorphous shape); however, after applying thermal annealing at 120 °C, the small molecule film domains crystallize verified by X-ray diffraction: structural geometry becomes a well-defined organized array. By using STS, the energy band diagrams of the semiconductor bulk heterojunction (blended film) at the donor-acceptor interface are determined; morphology and energy characteristics can be correlated with the organic solar cells (OSC) performance. When combining thermal treatment and solvent vapor annealing processes as described in previous literature by using other techniques, OSC devices based on DRCN5T show a very acceptable power conversion efficiency of 9.0%.

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Shang, Yuzhi, Zilong Wang, Daxiao Yang, Yaru Wang, Chaoke Ma, Minlong Tao, Kai Sun, Jiyong Yang, and Junzhong Wang. "Orientation Ordering and Chiral Superstructures in Fullerene Monolayer on Cd (0001)." Nanomaterials 10, no. 7 (July 3, 2020): 1305. http://dx.doi.org/10.3390/nano10071305.

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The structure of C60 thin films grown on Cd (0001) surface has been investigated from submonolayer to second monolayer regimes with a low-temperature scanning tunneling microscopy (STM). There are different C60 domains with various misorientation angles relative to the lattice directions of Cd (0001). In the (2√3 × 2√3) R30° domain, orientational disorder of the individual C60 molecules with either pentagon, hexagon, or 6:6 bond facing up has been observed. However, orientation ordering appeared in the R26° domain such that all the C60 molecules adopt the same orientation with the 6:6 bond facing up. In particular, complex chiral motifs composed of seven C60 molecules with clockwise or anticlockwise handedness have been observed in the R4° and R8° domains, respectively. Scanning tunneling spectroscopy (STS) measurements reveal a reduced HOMO–LOMO gap of 2.1 eV for the C60 molecules adsorbed on Cd (0001) due to the substrate screening and charge transfer from Cd to C60 molecules.

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Maccallini, E., G. Kalantzopoulos, T. Tsoufis, R. G. Agostino, G. Chiarello, V. Formoso, T. Caruso, A. Policicchio, D. Gournis, and E. Colavita. "Metallic Tin-Filling Effects on Carbon Nanotubes Revealed by Atomically Resolved Spectro-Microscopies." Journal of Nano Research 3 (October 2008): 1–6. http://dx.doi.org/10.4028/www.scientific.net/jnanor.3.1.

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The identification of features in the Local Density of States (LDOS) of carbon nanotubes (CNTs) obtained by Scanning Tunneling Spectroscopy (STS) is of great importance in order to understand their properties. In this work, Single- and Multi-Wall Carbon Nanotubes are compared with Multi-Wall CNTs filled with tin nanowires (Sn@CNTs) in order to investigate the effect on morphological and electronic properties of the CNTs metallic filling. The LDOS of CNTs, together with topology changes, is investigated by using spatially resolved STM/STS at room temperature and in air and compared to the LDOS of highly oriented pyrolitic graphite (HOPG). The LDOS of CNTs is dominated from different electronic states filling the C 2pσ-2pσ* band gap. The appearance of those states is linked to the diameter and the defects of the CNTs. In fact, Snnanowires encapsulation induces changes in the structure of the CNTs and the appearance of electronic states in the LDOS inside the band gap. A more extensive description of the samples is obtained depicting the morphological features and the vibrational structure on wider areas using Scanning Electron Microscopy (SEM) and Raman spectroscopy, respectively.

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Journal articles on the topic 'STS [Scanning tunneling spectroscopy]'

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