Electronic glass-transition and its application to micro-fabrication

众所周知，玻璃在加热时会发生所谓的玻璃化转变，而我们在1995年发现了电子玻璃化转变。本研究试图了解电子玻璃化转变的机制并开发其应用，所得结果可归纳如下：1.除了光之外，电子束和扫描隧道显微镜（STM）电子也可用于电子玻璃化转变的制造。具体而言，电子束和STM提供亚微米制造。2.不仅As_2S_3，而且其它含Ag和Cu的硫系玻璃也表现出类似的现象。相反，氧化物玻璃则没有这种现象，因为原子键的共价性较低。例如，自由载流子的产生是必要条件。尽管有了这些新的认识，但我们还不能理解为什么通过电子激发可以诱导出微观原子流等现象。我们需要新的实验技术来揭示玻璃的纳米尺度性质。目前正在进行进一步的研究。

It is well-known that a glass exhibits the so-called glass-transition when it is heated, while we discovered the electronic glass-transition in 1995. In the present study, we have tried to understand mechanisms of the electronic glass-transition and to develop its applications.Results obtained can be summarized as follows :1.In addition to light, electron beams and scanning-tunneling-microscope (STM) electrons can be used for fabrication through the electronic glass-transition. Specifically, electron beams an STMs afford submicron-fabrication. We have prepared microlenses and gratings using this phenomenon.2.Not only As_2S_3, but also other chalcogenide glasses containing Ag and Cu exhibit similar phenomena. In contrast, oxide glasses cannot exhibit such phenomena, since the atomic bond is less covalent.3.Many insights have been obtained for the mechanisms of the electronic glass-transition. For instance, generation of free carriers is a necessary condition.Despite these insights newly obtained, we cannot yet understand why phenomena such as micro atomic flows can be induced through electronic excitation. We need new experimental techniques which can reveal nano-scale properties of glasses. Further studies are now in progress.