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Title: Spatial Imaging of Two-Dimensional Electronic States in Semiconductor Quantum Wells

Abstract

We measure the spatial distribution of the local density of states (LDOS) at cleaved surfaces of InAs/GaSb isolated quantum wells and double quantum wells (DQWs) by low-temperature scanning tunneling spectroscopy. Distinct standing wave patterns of LDOS corresponding to subbands are observed. These LDOS patterns and subband energies agree remarkably well with simple calculations with tip-induced band bending. Furthermore, for the DQWs, coupling of electronic states between the quantum wells is also clearly observed.

Authors:
; ; ; ;  [1];  [1];  [2];  [1];  [3];  [3]
  1. NTT Basic Research Laboratories, NTT Corporation, Atsugi-shi, Kanagawa 243-0198 (Japan)
  2. (France)
  3. (Japan)
Publication Date:
OSTI Identifier:
20951195
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 13; Other Information: DOI: 10.1103/PhysRevLett.98.136802; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; GALLIUM ANTIMONIDES; INDIUM ARSENIDES; QUANTUM WELLS; SCANNING TUNNELING MICROSCOPY; SEMICONDUCTOR MATERIALS; SPATIAL DISTRIBUTION; SPECTROSCOPY; STANDING WAVES; TUNNEL EFFECT; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Suzuki, K., Kanisawa, K., Janer, C., Takashina, K., Fujisawa, T., Perraud, S., Laboratoire de Photonique et de Nanostructures, CNRS, 91460 Marcoussis, Hirayama, Y., SORST-JST, Kawaguchi-shi, Saitama 331-0012, and Tohoku University, Sendai-shi, Miyagi 980-8578. Spatial Imaging of Two-Dimensional Electronic States in Semiconductor Quantum Wells. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.136802.
Suzuki, K., Kanisawa, K., Janer, C., Takashina, K., Fujisawa, T., Perraud, S., Laboratoire de Photonique et de Nanostructures, CNRS, 91460 Marcoussis, Hirayama, Y., SORST-JST, Kawaguchi-shi, Saitama 331-0012, & Tohoku University, Sendai-shi, Miyagi 980-8578. Spatial Imaging of Two-Dimensional Electronic States in Semiconductor Quantum Wells. United States. doi:10.1103/PHYSREVLETT.98.136802.
Suzuki, K., Kanisawa, K., Janer, C., Takashina, K., Fujisawa, T., Perraud, S., Laboratoire de Photonique et de Nanostructures, CNRS, 91460 Marcoussis, Hirayama, Y., SORST-JST, Kawaguchi-shi, Saitama 331-0012, and Tohoku University, Sendai-shi, Miyagi 980-8578. Fri . "Spatial Imaging of Two-Dimensional Electronic States in Semiconductor Quantum Wells". United States. doi:10.1103/PHYSREVLETT.98.136802.
@article{osti_20951195,
title = {Spatial Imaging of Two-Dimensional Electronic States in Semiconductor Quantum Wells},
author = {Suzuki, K. and Kanisawa, K. and Janer, C. and Takashina, K. and Fujisawa, T. and Perraud, S. and Laboratoire de Photonique et de Nanostructures, CNRS, 91460 Marcoussis and Hirayama, Y. and SORST-JST, Kawaguchi-shi, Saitama 331-0012 and Tohoku University, Sendai-shi, Miyagi 980-8578},
abstractNote = {We measure the spatial distribution of the local density of states (LDOS) at cleaved surfaces of InAs/GaSb isolated quantum wells and double quantum wells (DQWs) by low-temperature scanning tunneling spectroscopy. Distinct standing wave patterns of LDOS corresponding to subbands are observed. These LDOS patterns and subband energies agree remarkably well with simple calculations with tip-induced band bending. Furthermore, for the DQWs, coupling of electronic states between the quantum wells is also clearly observed.},
doi = {10.1103/PHYSREVLETT.98.136802},
journal = {Physical Review Letters},
number = 13,
volume = 98,
place = {United States},
year = {Fri Mar 30 00:00:00 EDT 2007},
month = {Fri Mar 30 00:00:00 EDT 2007}
}
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