Wavelength extension beyond 1.5 micrometer in symmetric InAs quantum dots on InP(111)A using droplet epitaxy

TL;DR

This paper demonstrates wavelength tuning of symmetric InAs quantum dots on InP(111)A from 1.3 to 1.7 micrometers by adjusting barrier composition, enabling potential quantum-entangled photon sources.

Contribution

It introduces a method to control emission wavelength of symmetric quantum dots beyond 1.5 micrometers through barrier composition tuning on a (111) substrate.

Findings

Wavelength tunability from 1.3 to 1.7 micrometers achieved

Spectral shift matches numerical simulations

High structural symmetry suitable for quantum emitters

Abstract

By using a C3v symmetric (111) surface as a growth substrate, we are able to achieve high structural symmetry in self-assembled quantum dots, which are suitable for use as quantum-entangled photon emitters. Here we report on the wavelength controllability of InAs dots on InP(111)A, which we realized by tuning the ternary alloy composition of In(Al,Ga)As barriers that were lattice-matched to InP. We changed the peak emission wavelength systematically from 1.3 to 1.7 micrometer by barrier band gap tuning. The observed spectral shift agreed with the result of numerical simulations that assumed a measured shape distribution independent of barrier choice.