Shuhui Zhang, Lu Wang, Zhenwu Shi, Yanxiang Cui, Haitao Tian, Huaiju Gao, Haiqiang Jia, Wenxin Wang, Hong Chen, Liancheng Zhao
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, 150001, China.
Nanoscale Res Lett. 2012 Jan 25;7(1):87. doi: 10.1186/1556-276X-7-87.
We have investigated the structural and optical properties of type-II GaSb/InGaAs quantum dots [QDs] grown on InP (100) substrate by molecular beam epitaxy. Rectangular-shaped GaSb QDs were well developed and no nanodash-like structures which could be easily found in the InAs/InP QD system were formed. Low-temperature photoluminescence spectra show there are two peaks centered at 0.75eV and 0.76ev. The low-energy peak blueshifted with increasing excitation power is identified as the indirect transition from the InGaAs conduction band to the GaSb hole level (type-II), and the high-energy peak is identified as the direct transition (type-I) of GaSb QDs. This material system shows a promising application on quantum-dot infrared detectors and quantum-dot field-effect transistor.
我们通过分子束外延研究了在InP(100)衬底上生长的II型GaSb/InGaAs量子点[QDs]的结构和光学性质。矩形GaSb量子点发育良好，未形成在InAs/InP量子点系统中容易发现的纳米线结构。低温光致发光光谱显示有两个峰值，分别位于0.75eV和0.76eV处。随着激发功率增加而蓝移的低能峰被确定为从InGaAs导带到GaSb空穴能级的间接跃迁（II型），高能峰被确定为GaSb量子点的直接跃迁（I型）。这种材料系统在量子点红外探测器和量子点场效应晶体管方面显示出有前景的应用。
