论文标题
电子和孔掺杂拓扑的绝缘体材料$（BI_ {1-X} SB_ {X}）_ {2} TE_ {3} $
Relaxation dynamics of the optically driven nonequilibrium states in the electron- and hole-doped topological-insulator materials $(Bi_{1-x}Sb_{x})_{2}Te_{3}$
论文作者
论文摘要
我们报告有关拓扑 - 抑制剂材料$（BI_ {1-X} SB_ {X}）_ {2} TE_ {3} $的拓扑仪器材料$（BI_ {1-X} SB_ {3} $）的中红外泵terahertz-transmiss-transiss-trabe-trobe研究。发现弛豫动力学在各个方面都不同，在带隙下方或之上的过渡方面，通过更改泵 - 脉冲能量有选择性地兴奋。对于频带的激发，观察到泵探针信号的指数衰减，该衰减表现出对泵 - 脉冲脉冲的线性依赖性。相比之下，上带有频率激发的弛豫动力学的特征在于高泵射击处的压缩指数衰减和非线性的平稳性依赖性，这反映了激发的非平衡状态的相互作用。
We report on time-resolved mid-infrared-pump terahertz-transmission-probe studies of the topological-insulator materials $(Bi_{1-x}Sb_{x})_{2}Te_{3}$, in which by varying x charge carriers are chemically tuned to be of n-type or p-type. Relaxation dynamics is found to be different in various aspects for transitions below or above the bandgap, which are selectively excited by changing the pump-pulse energy. For the below-bandgap excitation, an exponential decay of the pump-probe signals is observed, which exhibits linear dependence on the pump-pulse fluence. In contrast, the relaxation dynamics for the above-bandgap excitation is characterized by a compressed exponential decay and nonlinear fluence dependence at high pump flunences, which reflects interaction of the excited nonequilibrium states.
