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Updated: Jul 11, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
One-dimensional band-edge absorption in a doped quantum wire
Toshiyuki Ihara1, Yuhei Hayamizu, Masahiro Yoshita
1Institute for Solid State Physics (ISSP), University of Tokyo, and CREST, JST, 5-1-5, Kashiwanoha, Kashiwa, 277-8581 Chiba, Japan. ihara@issp.u-tokyo.ac.jp
Physical Review Letters
|October 13, 2007
Summary
This study investigates quantum wires using photoluminescence. Researchers observed unique band-edge absorption and Fermi-edge absorption in one-dimensional electron gases.
Area of Science:
- Condensed matter physics
- Semiconductor nanostructures
Background:
- Quantum wires confine electrons in one dimension, leading to unique electronic properties.
- Modulation-doped structures allow for controlled tuning of electron densities.
Purpose of the Study:
- To investigate the photoluminescence-excitation spectra of n-type modulation-doped T-shaped single quantum wires.
- To understand the influence of tunable electron densities on the electronic states within the quantum wire.
Main Methods:
- Low-temperature photoluminescence-excitation spectroscopy.
- Utilizing a gate to control electron densities in the quantum wire.
Main Results:
- Observed sharp peak structures in band-edge absorption, characteristic of one-dimensional (1D) density of states in nondegenerate electron gases.
- Detected Fermi-edge absorption onset in degenerate 1D electron gases at low temperatures.
- Noted the absence of significant many-body modifications in the observed Fermi-edge absorption.
Conclusions:
- The study confirms the distinct electronic behavior of one-dimensional systems.
- The observed phenomena provide insights into the fundamental properties of electron gases in quantum confined structures.
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