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

Tham khảo tài liệu 'báo cáo hóa học: " the structural and optical properties of gasb/ingaas type-ii quantum dots grown on inp (100) substrate"', luận văn - báo cáo phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 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