Electrical and optical properties in rare earth-doped amorphous chalcogenides

硫系玻璃目前正被研究作为稀土掺杂光子器件的主介质，如光纤放大器或光纤激光器。由于低声子能量，高折射率和近红外高透明度，硫系玻璃是非常有吸引力的，并有潜力用于此类器件。本文采用溅射法制备了稀土掺杂硫系化合物（As2Se3）薄膜。研究了含稀土和不含稀土的材料的电学和光学性质。一般来说，硫系玻璃表现出各种光致效应，如缺陷产生和体积变化，因此这些基本性质被系统地研究了。为了了解从硫族化物到稀土离子的非辐射转变（能量传递机制未知），进行了噪声测量。这是世界上第一次。建立了测量系统，很快就会得到有用的结果。观察了稀土离子的光致发光。然而，目前信号非常微弱。这意味着样品仍然不合格。我的下一个目标是1)为了准备好的样品，应该寻找溅射的最佳条件。2)非辐射跃迁应发展噪声（1/f）理论。工程正在沿着这个目的进行。

Chalcogenide glasses are currently being investigated as host media for rare earthdoped photonic devices such as fiber amplifiers or fiber lasers. Due to low phonon energies, high rfractive index, and higher transparency in the near infrared, chalcogenide glasses are very attractive and have a potential for such devices.In the present study, the thin films of rare earth- doped chalcogenides (As2Se3) were tried to prepare by a sputtering method. The electrical and optical properties have been studied for both with and without rare earth (Pr) component. In general, chalcogenide glasses show various photoinduced effects such as defect creation and volume changes and hence these basic properties were systematically studied. To know nonradiative transition from chalcogenide to rare earth ions (energy transfer mechanisms are unknown), a noise measurements were undertaken. This is the first time in the world. The measurement system was established and the useful results will be obtained soon. The photoluminescence from rare earth ions were observed. The signal is however very weak at present. This means the sample is still not qualified.My next target is 1) To prepare good samples, the best condition for sputtering should be looked for. 2) The theory for noise (1/f) should be developed for nonradiative transition. The works are going on along this purpose.