In order to develop the photodetector for effective blue-green response, the 18-mm-diameter vacuum image tube combined with the transmission-mode Alo.7Gao.3Aso.9Po.1/GaAso.9Po.1 photocathode grown by molecular beam ep...In order to develop the photodetector for effective blue-green response, the 18-mm-diameter vacuum image tube combined with the transmission-mode Alo.7Gao.3Aso.9Po.1/GaAso.9Po.1 photocathode grown by molecular beam epitaxy is tentatively fabricated. A comparison of photoelectric property, spectral characteristic and performance parameter be- tween the transmission-mode GaAsP-based and blue-extended GaAs-based photocathodes shows that the GaAsP-based photocathode possesses better absorption and higher quantum efficiency in the blue-green waveband, combined with a larger surface electron escape probability. Especially, the quantum efficiency at 532 nm for the GaAsP-based photocathode achieves as high as 59%, nearly twice that for the blue-extended GaAs-based one, which would be more conducive to the underwater range-gated imaging based on laser illumination. Moreover, the simulation results show that the favorable blue-green response can be achieved by optimizing the emission-layer thickness in a range of 0.4 μm-0.6 μm.展开更多
Compared with the conventional strained quantum well, the InGaAs/GaAsP strain compensated quantum well (SCQW) has better optical properties, as the well layer and the barrier layer lattice mismatch with each other whi...Compared with the conventional strained quantum well, the InGaAs/GaAsP strain compensated quantum well (SCQW) has better optical properties, as the well layer and the barrier layer lattice mismatch with each other which results in the introduction of stress. In this paper, we adopted the Kohn-Luttinger Hamiltonian, conducted some theoretical calculations using the transfer matrix method, and finally verified the following change trend of the InGaAs quantum well following the In-group through experiments: the growth of the low In-group can improve the epitaxial flatness of the active area;the growth of the high In-group can increase the wavelength as well as the strain. In this paper, we adopted the AlGaAs barrier material instead of the GaAsP, made an analysis on the level changes of the compensation quantum well, and successfully fostered the strain compensated quantum well structure using the metal-organic chemical vapor deposition (MOCVD) system which had better optical properties compared with the strained quantum wells.展开更多
In order to improve the characteristics of the general broad-waveguide 808-nm semiconductor laser diode （LD）, we design a new type quantum well LD with an asymmetric cladding structure. The structure is grown by met...In order to improve the characteristics of the general broad-waveguide 808-nm semiconductor laser diode （LD）, we design a new type quantum well LD with an asymmetric cladding structure. The structure is grown by metal organic chemical vapor deposition （MOCVD）. For the devices with 100-ttm-wide stripe and 1000-/zm-long cavity under continuous-wave （CW） operation condition, the typical threshold current is 190 mA, the slope efficiency is 1.31 W/A, the wall-plug efficiency reaches 63%, and the maximum output power reaches higher than 7 W. And the internal absorption value decreases to 1.5 cm^-1.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61301023)the Science and Technology on Low-Light-Level Nigh Vision Laboratory Foundation,China(Grant No.BJ2014001)
文摘In order to develop the photodetector for effective blue-green response, the 18-mm-diameter vacuum image tube combined with the transmission-mode Alo.7Gao.3Aso.9Po.1/GaAso.9Po.1 photocathode grown by molecular beam epitaxy is tentatively fabricated. A comparison of photoelectric property, spectral characteristic and performance parameter be- tween the transmission-mode GaAsP-based and blue-extended GaAs-based photocathodes shows that the GaAsP-based photocathode possesses better absorption and higher quantum efficiency in the blue-green waveband, combined with a larger surface electron escape probability. Especially, the quantum efficiency at 532 nm for the GaAsP-based photocathode achieves as high as 59%, nearly twice that for the blue-extended GaAs-based one, which would be more conducive to the underwater range-gated imaging based on laser illumination. Moreover, the simulation results show that the favorable blue-green response can be achieved by optimizing the emission-layer thickness in a range of 0.4 μm-0.6 μm.
文摘Compared with the conventional strained quantum well, the InGaAs/GaAsP strain compensated quantum well (SCQW) has better optical properties, as the well layer and the barrier layer lattice mismatch with each other which results in the introduction of stress. In this paper, we adopted the Kohn-Luttinger Hamiltonian, conducted some theoretical calculations using the transfer matrix method, and finally verified the following change trend of the InGaAs quantum well following the In-group through experiments: the growth of the low In-group can improve the epitaxial flatness of the active area;the growth of the high In-group can increase the wavelength as well as the strain. In this paper, we adopted the AlGaAs barrier material instead of the GaAsP, made an analysis on the level changes of the compensation quantum well, and successfully fostered the strain compensated quantum well structure using the metal-organic chemical vapor deposition (MOCVD) system which had better optical properties compared with the strained quantum wells.
基金supported by the National Natural Science Foundation of China (No.50472068)the Program for New Century Excellent Talents in University
文摘In order to improve the characteristics of the general broad-waveguide 808-nm semiconductor laser diode （LD）, we design a new type quantum well LD with an asymmetric cladding structure. The structure is grown by metal organic chemical vapor deposition （MOCVD）. For the devices with 100-ttm-wide stripe and 1000-/zm-long cavity under continuous-wave （CW） operation condition, the typical threshold current is 190 mA, the slope efficiency is 1.31 W/A, the wall-plug efficiency reaches 63%, and the maximum output power reaches higher than 7 W. And the internal absorption value decreases to 1.5 cm^-1.
