Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral range.Despite the fact that they already achieved ...Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral range.Despite the fact that they already achieved notable success,the performance suffers from the thermionic emission of electrons from the quantum dots at elevated temperatures resulting in a decreasing responsivity.In order to provide an efficient carrier injection at high temperatures,quantum dot infrared photodetectors can be separated into two parts:an injection part and a detection part,so that each part can be separately optimized.In order to integrate such functionality into a device,a new class of quantum dot infrared photodetectors using quantum dot molecules will be introduced.In addition to a general discussion simulation results suggest a possibility to realize such a device.展开更多
本文报道了采用分子束外延技术制备的三色In As/Ga As量子点红外探测器.器件采用nin型结构,吸收区结构是在In Ga As量子阱中生长含有Al Ga As插入层的In As量子点,器件在77 K下的红外光电流谱有三个峰值:6.3,10.2和11μm.文中分析了它...本文报道了采用分子束外延技术制备的三色In As/Ga As量子点红外探测器.器件采用nin型结构,吸收区结构是在In Ga As量子阱中生长含有Al Ga As插入层的In As量子点,器件在77 K下的红外光电流谱有三个峰值:6.3,10.2和11μm.文中分析了它们的跃迁机制,并且分别进行了指认.因为有源区采用了不对称结构,所以器件在外加偏压正负方向不同时,光电流谱峰值的强度存在一些差异.不论在正偏压或者负偏压下,当偏压达到较高值,再进一步增大偏压时,都出现了对应于连续态的跃迁峰强度明显下降的现象,这是由量子点基态与阱外连续态的波函数交叠随着偏压进一步增大而迅速减小导致的.展开更多
文摘Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral range.Despite the fact that they already achieved notable success,the performance suffers from the thermionic emission of electrons from the quantum dots at elevated temperatures resulting in a decreasing responsivity.In order to provide an efficient carrier injection at high temperatures,quantum dot infrared photodetectors can be separated into two parts:an injection part and a detection part,so that each part can be separately optimized.In order to integrate such functionality into a device,a new class of quantum dot infrared photodetectors using quantum dot molecules will be introduced.In addition to a general discussion simulation results suggest a possibility to realize such a device.
文摘本文报道了采用分子束外延技术制备的三色In As/Ga As量子点红外探测器.器件采用nin型结构,吸收区结构是在In Ga As量子阱中生长含有Al Ga As插入层的In As量子点,器件在77 K下的红外光电流谱有三个峰值:6.3,10.2和11μm.文中分析了它们的跃迁机制,并且分别进行了指认.因为有源区采用了不对称结构,所以器件在外加偏压正负方向不同时,光电流谱峰值的强度存在一些差异.不论在正偏压或者负偏压下,当偏压达到较高值,再进一步增大偏压时,都出现了对应于连续态的跃迁峰强度明显下降的现象,这是由量子点基态与阱外连续态的波函数交叠随着偏压进一步增大而迅速减小导致的.
