Pashchenko Alexander S, Lunin Leonid S, Danilina Eleonora M, Chebotarev Sergei N
Laboratory of Nanotechnology and Solar Energy, Federal Research Center Southern Scientific Center of Russian Academy of Sciences, 344006, 41, Chekhov Avenue, Rostov-on-Don, Russia.
Department of Physics and Electronics, Platov South-Russian State Polytechnic University (NPI), 346428, 132, Prosveshchenia str., Novocherkassk, Russia.
Beilstein J Nanotechnol. 2018 Nov 2;9:2794-2801. doi: 10.3762/bjnano.9.261. eCollection 2018.
This work reports on an experimental investigation of the influence of vertical stacking of quantum dots, the thickness of GaAs potential barriers, and their isovalent doping with bismuth on the photoluminescence properties of InAs/GaAs heterostructures. The experimental samples were grown by ion-beam deposition. We showed that using three vertically stacked layers of InAs quantum dots separated by thin GaAs barrier layers was accompanied by a red-shift of the photoluminescence peak of InAs/GaAs heterostructures. An increase in the thickness of the GaAs barrier layers was accompanied by a blue shift of the photoluminescence peak. The effect of isovalent Bi doping of the GaAs barrier layers on the structural and optical properties of the InAs/GaAs heterostructures was investigated. It was found that the Bi content up to 4.96 atom % in GaAs decreases the density of InAs quantum dots from 1.53 × 10 to 0.93 × 10 cm. In addition, the average lateral size of the InAs quantum dots increased from 14 to 20 nm, due to an increase in the surface diffusion of In. It is shown that isovalent doping of GaAs potential barriers by bismuth was accompanied by a red-shift of the photoluminescence peak of InAs quantum dots of 121 meV.
本工作报道了关于量子点垂直堆叠、GaAs势垒厚度及其铋等电子掺杂对InAs/GaAs异质结构光致发光特性影响的实验研究。实验样品通过离子束沉积生长。我们表明，使用由薄GaAs势垒层隔开的三层垂直堆叠的InAs量子点会伴随着InAs/GaAs异质结构光致发光峰的红移。GaAs势垒层厚度的增加伴随着光致发光峰的蓝移。研究了GaAs势垒层的铋等电子掺杂对InAs/GaAs异质结构的结构和光学性质的影响。发现GaAs中铋含量高达4.96原子%时，InAs量子点的密度从1.53×10降至0.93×10 cm。此外，由于In表面扩散的增加，InAs量子点的平均横向尺寸从14 nm增加到20 nm。结果表明，铋对GaAs势垒层的等电子掺杂伴随着InAs量子点光致发光峰红移121 meV。
