tailieunhanh - báo cáo hóa học:" The structural and optical properties of GaSb/InGaAs type-II quantum dots grown on InP (100) substrate"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: The structural and optical properties of GaSb/InGaAs type-II quantum dots grown on InP (100) substrate | Shuhui et al. Nanoscale Research Letters 2012 7 87 http content 7 1 87 o Nanoscale Research Letters a SpringerOpen Journal ORIGINAL PAPER Open Access The structural and optical properties of GaSb InGaAs type-II quantum dots grown on InP 100 substrate 2 2 s 2 2 2 Zhang Shuhui 1 Wang Lu Shi Zhenwu Cui Yanxiang Tian Haitao Gao Huaiju Jia Haiqiang Wang Wenxin2 Chen Hong2 and Zhao Liancheng1 Abstract 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 and . 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. Introduction Quantum-size nanostructure materials have always been the research focus 1-5 . In recent years staggered lineup type-II quantum-size nanostructures are of great research interest due to their possible application in many novel devices 6 7 . Notably a large research effort has been focused on the type-II quantum-size nanostructures composed of III and V direct-bandgap semiconductor materials such as GaSb GaAs 8-10 InAlAs InP 11 InP InGaP 12 13 InP GaAs 14 GaAsSb GaAs 15 and InAs GaSb 16 17 . The reason is that they offer comparatively large bandgap energies and provide a possibility of covering the whole middle and far-infared optical range for photoelectric devices. Among these material systems GaSb GaAs quantum dot QD is an outstanding representative since its giant