Topic
Scanning tunneling spectroscopy
About: Scanning tunneling spectroscopy is a research topic. Over the lifetime, 7886 publications have been published within this topic receiving 213828 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the electronic properties at the interface of a PTCDA molecular film on Au(1 1 1 ) were studied by means of scanning tunneling microscopy (STM) and angle resolved ultraviolet photoelectron spectroscopy (ARUPS).
102 citations
TL;DR: In this article, the authors used scanning tunneling spectroscopy to study the superconductor-insulator phase transition in homogeneously disordered ultrathin (2-15 nm) films of NbN.
Abstract: Using scanning tunneling spectroscopy, we address the problem of the superconductor-insulator phase transition in homogeneously disordered ultrathin (2-15 nm) films of NbN. Samples thicker than 8 nm, for which the Ioffe-Regel parameter k(F)l >= 5.6, manifest a conventional superconductivity: a spatially homogeneous BCS-like gap, vanishing at the critical temperature, and a disordered vortex lattice in magnetic field. Upon thickness reduction, however, while k(F)l lowers, the STS reveals striking deviations from the BCS scenario, among which a progressive decrease of the coherence peak height and small spatial inhomogeneities. In addition, the gap below T-C develops on a spectral background, which becomes more and more ``V-shaped'' approaching the localization. The thinnest film (2.16 nm), while not being exactly at the superconductor-insulator transition (SIT) (T-C approximate to 0.4T(C)(bulk)), showed unconventional signatures such as the vanishing of the coherence peaks and the absence of vortices. This behavior suggests a weakening of long-range phase coherence, when approaching the SIT in this quasi-2D limit.
102 citations
TL;DR: The existence of static striped density of electronic states in nearly optimally doped Bi2Sr2CaCu2O8+δ in zero field is shown, and the density of states modulation manifests itself as a shift of states from above to below the superconducting gap.
Abstract: In this article we show, using scanning tunneling spectroscopy, the existence of static striped density of electronic states in nearly optimally doped Bi2Sr2CaCu2O8+delta in zero field. This modulation is aligned with the Cu-O bonds, with a periodicity of four lattice constants, and exhibits features characteristic of a two-dimensional system of line objects. We further show that the density of states modulation manifests itself as a shift of states from above to below the superconducting gap. The fact that a single energy scale (i.e., the gap) appears for both superconductivity and stripes suggests that these two effects have the same origin.
101 citations
IBM1
TL;DR: Analysis of maps of the integral photon intensity emitted from the tunneling gap of a scanning tunneling microscope obtained simultaneously with topography from a variety of metal films and single-crystal surfaces in ultrahigh vacuum suggests that contrasts in photon maps on a scale of some tens of nanometers are attributable to local variations in the field strength of tip-induced plasmon modes.
Abstract: We analyze maps of the integral photon intensity emitted from the tunneling gap of a scanning tunneling microscope obtained simultaneously with topography from a variety of metal films and single-crystal surfaces in ultrahigh vacuum. The effects of adsorbates and structures created with the scanning tunneling microscope on their local photon emission properties are investigated to explore the potential of the technique for chemical mapping. It is proposed that contrasts in photon maps on a scale of some tens of nanometers are attributable to local variations in the field strength of tip-induced plasmon modes which are determined by the surface geometry of the junction and its dielectric properties. On a (sub)nanometer scale, a second contrast mechanism is observed to occur, consistent with geometry-induced variations in the matrix element for inelastic tunneling. A comparison of electron spectroscopic data with bias-dependent photon maps indicates that contrasts on a subnanometer scale are further mediated by local modifications of the density of final states positioned one quantum of energy (h\ensuremath{
u}) below the bottom of the elastic tunneling channel with respect to the Fermi level. These three mechanisms provide a framework for the interpretation of photon maps obtained on metallic systems.
101 citations
TL;DR: In this article, a dual-probe scanning tunneling microscope (D-STM) was used to elucidate the electric property of a sample with a spatial resolution of ∼1 nm.
Abstract: We have constructed a dual-probe scanning tunneling microscope (D-STM). We used multiwall carbon nanotubes [(NT), diameter: ∼10 nm] as STM probes. The D-STM allows us to elucidate the electric property of a sample with a spatial resolution of ∼1 nm. Using this system, we have measured the current–voltage curves of a single NT ring as a transistor. The curves show the possibility of nanometer-scale electronic circuits composed of NT devices.
101 citations