OPTICAL CHARACTERISTICS INVESTIGATION ON COMPOUND SEMICONDUCTOR NATIVE DEFECTS AND RELATED MATERIALS

对半绝缘砷化镓、红外发光荧光粉和掺铒硅玻璃纤维等材料的发光和光吸收特性进行了研究。以前已经证明，半绝缘砷化镓的天然缺陷可以用回收特性、漂白特性和吸收特性来表征。这些类型的特征程序正在扩展到检查二维空间分布特征。这项研究工作正在继续进行。对稀土活化红外发光荧光粉进行了系统的研究。研究表明，具有氟晶格的铒活化荧光粉在2.6 ~ 2.8um波长范围内具有较强的发光。研究表明，如果将这些荧光粉与GaAs:Si红外发光二极管和PbS光导探测器结合使用，则可以提供简单方便的大气水汽传感器探测装置。探索波长较长的发光材料的研究仍在继续。研究了掺铒硅玻璃纤维的放大自发发射特性。采用氩离子激光作为激发源进行测量。已经相当确定的是，来自较高能级的波长转换过程并不完全是先前假设的非辐射衰减过程，而是很大程度上归因于中间辐射衰减过程。

Investigations have been carried out for luminescence as well as optical absorption characteristics of several interesting materials including semi-insulating GaAs, infrared emitting phosphors and Er-doped silica glass fiber.It has been previously demonstrated that the native defects in semi-insulating GaAs can be characterized by recovery characteristics as well as bleaching and absorption characteristics. These kinds of characterizing procedures are being extended for examining two dimensional, spatial distribution characteristics. This research work is being continued.Systematic investigations on rare earth-activated, infrared emitting phosphors have been carried out. It has been shown that Er-activated phosphors having flouride lattices present fairly intense luminescence at 2.6 to 2.8um wavelength region. It has been demonstrated that these phosphors present simple and convenient detecting device for atmospheric water vapor sensor, if combined with GaAs:Si infrared light emitting diode and PbS photoconductive detector. Research activity is still continued for exploring longer wavelength emitting light materials.Examinations have been performed on amplified spontaneous emission characteristics in Er-doped, silica glass fiber. The measurements were carried out by using Ar ion laser as excitation source. It has been fairly established that the wavelength conversion processes from higher levels are not solely nonradiative decay process as previously postulated but considerably due to intermediate radiative decay process.