Optical Measurements and Theoretical Modelling of Excitons in Double ZnO/ZnMgO Quantum Wells in an Internal Electric Field

Materials

Janusz Andrzejewski¹  Mieczyslaw Antoni Pietrzyk²  Adrian Kozanecki²  Dawid Jarosz² 

[1] Department of Experimental Physics, Faculty of Fundamental Problems of Technology, Wrocław University of Science and Technology, ul. Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland;Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warsaw, Poland;

关键词: semiconductors;    ZnO;    photoluminescence;    excitons;    effective-mass theory;   

DOI  :  10.3390/ma14237222

来源: DOAJ

【 摘 要 】

In this paper, the photoluminescence spectra of excitons in ZnO/ZnMgO/ZnO double asymmetric quantum wells grown on a–plane ${\mathrm{Al}}_2{\mathrm{O}}_3$ substrates with internal electric-field bands structures were studied. In these structures, the electron and the hole in the exciton are spatially separated between neighbouring quantum wells, by a ZnMgO barrier with different thickness. The existence of an internal electric field generates a linear potential and, as a result, lowers the energy of quantum states in the well. For the wide wells, the electrons are spatially separated from the holes and can create indirect exciton. To help the understanding of the photoluminescence spectra, for single particle states the 8 k·p for wurtzite structure is employed. Using these states, the exciton in the self-consistent model with 2D hydrogenic 1s–like wave function is calculated.

【 授权许可】

Unknown