Strong photo-absorption by a single quantum wire in waveguide-transmission spectroscopy

TL;DR

This study demonstrates that a single quantum wire embedded in an optical waveguide exhibits strong photo-absorption, with a high absorption coefficient and probability, using waveguide-transmission spectroscopy at low temperature.

Contribution

It provides the first measurement of absorption spectrum of a single quantum wire in a waveguide, revealing significant absorption despite its small volume.

Findings

High absorption coefficient of 80 /cm observed.

98% absorption probability for a 500-um waveguide.

Effective single-wire optical absorption demonstrated.

Abstract

We measured the absorption spectrum of a single T-shaped, 14x6 nm lateral-sized quantum wire embedded in an optical waveguide using waveguide-transmission spectroscopy at 5 K. In spite of its small volume, the one-dimensional-exciton ground state shows a large absorption coefficient of 80 /cm, or a 98 % absorption probability for a single pass of the 500-um-long waveguide.