Hole diffusivity in GaAsBi alloys measured by a picosecond transient grating technique
Hole diffusivity in GaAsBi alloys measured by a picosecond transient grating technique
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DOI：
10.1063/1.3557047
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发表时间：
2011-02
影响因子：
4
通讯作者：
S. Nargelas;K. Jarašiūnas;K. Bertulis;V. Pačebutas
中科院分区：
文献类型：
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作者：
S. Nargelas;K. Jarašiūnas;K. Bertulis;V. Pačebutas
我们应用时间分辨瞬态光栅技术研究了x= 0.025-0.063的GaAs1−xBix合金中的非平衡载流子动力学。观察到载流子双极扩散系数随温度降低而降低，其饱和度低于80 K，表明非平衡空穴的强烈局域化。室温下的热活化能ΔEa=46 meV的扩散率和低空穴迁移率μh= 10-20 cm2/V s证实了局域Bi态与GaAs价带的杂化模型。载流子复合率随Bi含量的非线性增加（1/τR∝Bi(x)3.2）表明合金的结构无序性增加。
We applied a time-resolved transient grating technique for investigation of nonequilibrium carrier dynamics in GaAs1−xBix alloys with x=0.025–0.063. The observed decrease in carrier bipolar diffusivity with lowering temperature and its saturation below 80 K revealed a strong localization of nonequilibrium holes. Thermal activation energy ΔEa=46 meV of diffusivity and low hole mobility value μh=10–20 cm2/V s at room temperature confirmed the hybridization model of the localized Bi states with the valence band of GaAs. Nonlinear increase in carrier recombination rate with the Bi content, 1/τR∝Bi(x)3.2 indicated an increasing structural disorder in the alloy.