A novel kind of multi-quantum well infrared photodetector（QWlP） is presented. In the new structure device,a p-type contact layer has been grown on the top of the conventional structure of QWlP,then a small tunneling...A novel kind of multi-quantum well infrared photodetector（QWlP） is presented. In the new structure device,a p-type contact layer has been grown on the top of the conventional structure of QWlP,then a small tunneling current is instead of the large compensatory current,which made the device low dark current and low noise characteristics. The measured result of dark current is consistent with the calculated result, and the noise of the new structure QWIP is decreased to one third of the conventional QWlP.展开更多
The temperature characteristics for the different lasing modes at 300 K of intracavity contacted InGaAs/GaAs Vertical Cavity Surface Emitting Lasers（VCSELs） have been investigated experimentally by using the SV-32 c...The temperature characteristics for the different lasing modes at 300 K of intracavity contacted InGaAs/GaAs Vertical Cavity Surface Emitting Lasers（VCSELs） have been investigated experimentally by using the SV-32 cryostat and LD200205 test system. In combination with the simulation results of the reflective spectrum and the gain peak at different temperatures, the measurement results have been analyzed. In addition, the dependence of device size on temperature characteristics is discussed. The experimental data can be used to optimally design of VCSEL at high or cryogenic temperature.展开更多
A new structure of high-brightness light-emitting diodes(LED)is experimentally demonstrated.The thin window layer is composed of a 300-nm-thick indium-tin-oxide layer and a 500-nm-thick GaP layer for both current spre...A new structure of high-brightness light-emitting diodes(LED)is experimentally demonstrated.The thin window layer is composed of a 300-nm-thick indium-tin-oxide layer and a 500-nm-thick GaP layer for both current spreading and light anti-reflection.The two coupled distributed Bragg reflectors(DBRs)with one for reflecting normal incidence light and the other for reflecting inclined incidence light which is emitted to the GaAs substrate are employed in the LED fabrication.The coupled DBRs in the LED can provide high reflectivity with wide-angle reflection.The efficiency-enhanced AlGaInP LED has the luminance intensity increase of more than 50%compared with conventional LEDs and high reliability with the saturation current 130 mA.展开更多
By introducing multi-leaf sectorial holes into an oxidation confined 850 nm vertical cavity surface emitting laser(VCSEL),the far-field divergence angle is reduced.The finite-difference time-domain method is used to s...By introducing multi-leaf sectorial holes into an oxidation confined 850 nm vertical cavity surface emitting laser(VCSEL),the far-field divergence angle is reduced.The finite-difference time-domain method is used to simulate the far-field pattern of the multi-leaf holey VCSEL with different etching depths and different shapes of the oxide aperture in diameter R.Based on the simulation result,we design and fabricate a multi−leaf holey VCSEL and its divergence angle is only 6°.The experimental results agree well with the theoretical predication.展开更多
文摘A novel kind of multi-quantum well infrared photodetector（QWlP） is presented. In the new structure device,a p-type contact layer has been grown on the top of the conventional structure of QWlP,then a small tunneling current is instead of the large compensatory current,which made the device low dark current and low noise characteristics. The measured result of dark current is consistent with the calculated result, and the noise of the new structure QWIP is decreased to one third of the conventional QWlP.
文摘The temperature characteristics for the different lasing modes at 300 K of intracavity contacted InGaAs/GaAs Vertical Cavity Surface Emitting Lasers（VCSELs） have been investigated experimentally by using the SV-32 cryostat and LD200205 test system. In combination with the simulation results of the reflective spectrum and the gain peak at different temperatures, the measurement results have been analyzed. In addition, the dependence of device size on temperature characteristics is discussed. The experimental data can be used to optimally design of VCSEL at high or cryogenic temperature.
基金by the National High-Technology Research and Development Program of China under Grant No 2006AA03A121the National Basic Research Program of China under Grant No 2006CB604902.
文摘A new structure of high-brightness light-emitting diodes(LED)is experimentally demonstrated.The thin window layer is composed of a 300-nm-thick indium-tin-oxide layer and a 500-nm-thick GaP layer for both current spreading and light anti-reflection.The two coupled distributed Bragg reflectors(DBRs)with one for reflecting normal incidence light and the other for reflecting inclined incidence light which is emitted to the GaAs substrate are employed in the LED fabrication.The coupled DBRs in the LED can provide high reflectivity with wide-angle reflection.The efficiency-enhanced AlGaInP LED has the luminance intensity increase of more than 50%compared with conventional LEDs and high reliability with the saturation current 130 mA.
基金by the National High Technology Research and Development Program of China under Grant No 2008AA03Z402the National Natural Science Foundation of China under Grant No 61076044the Natural Science Foundation of Beijing under Grant Nos 4092007,4102003 and 4112006.
文摘By introducing multi-leaf sectorial holes into an oxidation confined 850 nm vertical cavity surface emitting laser(VCSEL),the far-field divergence angle is reduced.The finite-difference time-domain method is used to simulate the far-field pattern of the multi-leaf holey VCSEL with different etching depths and different shapes of the oxide aperture in diameter R.Based on the simulation result,we design and fabricate a multi−leaf holey VCSEL and its divergence angle is only 6°.The experimental results agree well with the theoretical predication.
