Picosecond transient orientational and concentration gratings in germanium
Picosecond transient orientational and concentration gratings in germanium
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皮秒瞬态锗光栅和浓度光栅
DOI：
10.1109/jqe.1983.1071920
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发表时间：
1983
影响因子：
2.5
通讯作者：
A. Miller
中科院分区：
文献类型：
--
作者：
A. Smirl;T. Boggess;B. Wherrett;G. Perryman;A. Miller
我们提出并讨论了皮秒瞬态光栅自衍射测量锗的结果，可以理解的各向异性（在k空间）状态填充产生的取向光栅。虽然有预测和间接的实验证据，各向同性状态填充锗，这是第一个直接的实验表明，各向异性状态填充在半导体。我们比较了来自取向光栅的自衍射信号与来自带填充引起的浓度光栅的自衍射信号，并发现了几个区别，所有这些都可以用在前面的论文中发展的理论来解释。此外，我们还进行了三脉冲瞬态光栅寿命测量，结果表明浓度光栅衰减为数十皮秒，而取向光栅衰减太快，无法用我们的8 ps脉冲来解决。
We present and discuss the results of picosecond transient grating self-diffraction measurements in germanium that can be understood in terms of an orientational grating produced by anisotropic (in k space) state-filling. Although there have been predictions and indirect experimental evidence for isotropic state-filling in germanium, this is the first direct experimental indication of anisotropic state-filling in a semiconductor. We compare the self-diffracted signals from orientational gratings with those from band-filling induced concentration gratings and find several distinctions, all of which can be explained in terms of the theory developed in the preceding paper. In addition, we have performed three-pulse transient grating lifetime measurements which indicate that the concentration grating decay is tens of picoseconds, while the orientational grating decay is too rapid to resolve with our 8 ps pulses.