Miniband formation engineering in GaN/AlN constant total effective radius multi-shells quantum dots and rings with on-center hydrogenic donor impurities
Authors
Abstract:
In this work, we have studied the miniband and minigaps of GaN/AlN constant total effective radius multi-shells quantum dots (CTER-MSQDs) and Rings (CTERMSQRs).We have investigated effects of the Hydrogenic donor impurities, quantum dots and rings radii, and the number of wells on miniband formation by sub-band energy calculations. We show that in these systems, minigaps can be created and then disappeared when the number of wells increases. We observe that cylindrical CTER-MSQDs have one miniband more than the spherical CTER-MSQD. However, minibands of the cylindrical CTER-MSQD are wider. For cylindrical systems, the first minigap position can undertake a blue shift but for spherical systems, we can not observe this fact. The first minigap position undertakes moreblue shifts when the inner QD radius R1 increases. Thus, the number of wells, Hydrogenic donor impurities, and quantum dot & ring radii can be used as tuning tools to have a system with the typical number of minibands and minigaps with desired widths.
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Journal title
volume 2 issue 2
pages 195- 201
publication date 2019-05-01
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