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

• Published in: Applied physics letters Vol. 115; no. 20
• Main Authors: Mintairov, A. M., Lebedev, D. V., Bert, N., Belyaev, K. G., Nevedomskiy, V. N., Rakhlin, M. V., Toropov, A. A., Vlasov, A. S., Gocalinska, A., Juska, G., Pelucchi, E., Arredondo, M. A., Naden, A. B., Shelaev, A. V., Bykov, V. A.
• Format: Journal Article
• Language: English
• Published: 11.11.2019
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.5126527

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.