One-dimensional continuum and exciton states in quantum wires

TL;DR

This paper reports the fabrication and optical characterization of high-quality T-shaped quantum wires, revealing detailed properties of one-dimensional exciton and continuum states through micro-photoluminescence and excitation spectroscopy.

Contribution

It introduces a method for fabricating uniform quantum wires and provides detailed spectroscopic analysis of their 1-D exciton and continuum states.

Findings

High uniformity and sharp spectral features of quantum wires.

Observation of a large ground-state exciton peak in PLE spectrum.

Identification of 1-D continuum states with an onset 11 meV above excitons.

Abstract

High-quality T-shaped quantum wires are fabricated by cleaved-edge overgrowth with the molecular beam epitaxy on the interface improved by a growth-interrupt high-temperature anneal. Characterization by micro-photoluminescence (PL) and PL excitation (PLE) spectroscopy at 5 K reveals high uniformity, a sharp spectral width, and a small Stokes shift of one-dimensional (1-D) excitons. The PLE spectrum for 1-D states shows a large peak of ground-state excitons and a small absorption band ascribed to 1-D continuum states with an onset at 11 meV above the exciton peak.