Optical characteristics of single wavelength-tunable InAs/InGaAsP/InP(100) quantum dots emitting at 1.55 um

TL;DR

This study investigates the optical emission properties of single InAs quantum dots emitting at 1.55 μm, demonstrating their potential for fiber-based quantum communication due to stable emission characteristics up to 70 K.

Contribution

The paper provides detailed characterization of InAs quantum dots grown on InP(100), highlighting their exciton-biexciton behavior, temperature stability, and lack of fine structure splitting, advancing quantum dot applications.

Findings

Emission at 1550 nm with exciton-biexciton features

Stable emission up to 70 K without fine structure splitting

Negligible phonon-induced broadening up to 50 K

Abstract

We have studied the emission properties of individual InAs quantum dots (QDs) grown in an InGaAsP matrix on InP(100) by metal-organic vapor-phase epitaxy. Low-temperature microphotoluminescence spectroscopy shows emission from single QDs around 1550 nm with characteristic exciton-biexciton behavior, and a biexciton antibinding energy of more than 2 meV. Temperature-dependent measurements reveal negligible optical-phonon induced broadening of the exciton line up to 50 K, and emission from the exciton state clearly persists above 70 K. Furthermore, we find no measurable polarized fine structure splitting of the exciton state within the experimental precision. These results are encouraging for the development of a controllable photon source for fiber-based quantum information and cryptography systems.