Atomic ordering and bond relaxation in optical spectra of self-organized InP/GaInP2 Wigner molecule structures

A M Mintairov,A Gocalinska,V N Nevedomskiy,A V Shelaev,V A Bykov,D V Lebedev,E Pelucchi,M A Arredondo,A B Naden,G Juska,N Bert,K G Belyaev,A S Vlasov,M V Rakhlin,A A Toropov

doi:10.1063/1.5126527

Abstract

We used transmission electron microscopy, Raman, and photoluminescence spectroscopy to identify the effect of CuPt-type GaP-InP atomic ordering (AO) on the structural and emission properties of self-organized (SO) InP/GaInP2 Wigner molecule (WM) quantum dot (QD) structures. We found that the correlation of AO and SO growth results in the formation of InP/GaInP2 QD/AO-domain (QD/AOD) core-shell composites. This observation shows that intrinsic WMs in this system emerge due to a strong piezoelectric field generated by AODs, which induces QD doping and a built-in magnetic field. We found that the bond relaxation of AODs leads to a decrease in the emission energy of WMs of 80 meV. The photoluminescence spectra of single WMs having an emission energy ∼1.53 eV are presented here, the lowest one reported for this system.

Highlights

These quantum dot (QD) represent natural two-dimensional electron/ quantum Hall puddles and/or electron/composite fermion8 Wigner molecules (WMs)9 and are interesting for fundamental and applied research in quantum physics, nanoelectronics, and conventional5 and fault tolerant topologically protected10 quantum computing
We used transmission electron microscopy, Raman, and photoluminescence spectroscopy to identify the effect of CuPt-type GaP-InP atomic ordering (AO) on the structural and emission properties of self-organized (SO) InP/GaInP2 Wigner molecule (WM) quantum dot (QD) structures
We found that the correlation of AO and SO growth results in the formation of InP/GaInP2 QD/AO-domain (QD/AO domains (AODs)) core-shell composites

Summary

Introduction

These QDs represent natural two-dimensional electron/ quantum Hall puddles and/or electron/composite fermion8 Wigner molecules (WMs)9 and are interesting for fundamental and applied research in quantum physics, nanoelectronics, and conventional5 and fault tolerant topologically protected10 quantum computing. We used transmission electron microscopy (TEM), Raman, and temperature dependent l-PL spectroscopy measurements, including near-field scanning PL, to study the effect of CuPtB-type AODs on the structural and emission properties of InP/GaInP2 SO QD structures grown by low pressure MOVPE.21 Using cross section TEM

Results

Conclusion