The excitonic photoluminescence mechanism and lasing action in band-gap-tunable CdS(1-x)Se(x) nanostructures.
Bandgap tunable semiconductor materials have wide application in integrated-optoelectronic and communication devices. The CdS1-xSex ternary semiconductor materials covering green-red bands have been reported previously, but their basic band-gap and optical properties crucial to the performance of the CdS1-xSex-based optoelectronic devices have not been deeply understood. In this paper, we theoretically simulated and discussed the feasibility of bandgap-tunable CdS1-xSex nanomaterials for designing wavelength tunable microlasers. Then we fabricated the CdS1-xSex nanobelts with their band gap ranging from 2.4 to 1.74 eV by adjusting the composition ratio x in the vapor-phase-transport growth process. The temperature-dependent photoluminescence and exciton-related optical constants of the CdS1-xSex nanobelts were carefully demonstrated. Finally, the wavelength-tunable Fabry-Perot lasing in CdS1-xSex nanobelts was obtained, and the Fabry-Perot lasing mechanism was numerically simulated by the FDTD method. The systematic results on the mechanism of the tunable band gap, exciton properties and lasing of the CdS1-xSex nanostructure help us deeply understand the intrinsic optical properties of this material, and will build a strong foundation for future application of green-red wavelength-tunable CdS1-xSex microlasers.
State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, China. xcxseu@seu.edu.cn and Department of Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China. daijun@just.edu.cn.
Jun
J
Dai
Department of Physics, Nantong University, Nantong, 226019, China.
Pengxia
P
Zhou
State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, China. xcxseu@seu.edu.cn.
Junfeng
J
Lu
Department of Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China. daijun@just.edu.cn.
Hongge
H
Zheng
Department of Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China. daijun@just.edu.cn.
Jiyuan
J
Guo
Department of Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China. daijun@just.edu.cn.
Fang
F
Wang
State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, China. xcxseu@seu.edu.cn.
Ning
N
Gu
State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, China. xcxseu@seu.edu.cn.
Chunxiang
C
Xu