The presence of trap states plays an important role in the performance of opto-electronic devices. In the present investigation, charge carrier dynamics of newly synthesized amorphous and crystalline In$ {2} $Se$ {3} $ thin films have been carried out using broad band femtosecond pump-probe spectroscopy in the temperature range of 5-300 K. Amorphous In$ {2} $Se$ {3} $ thin films (thickness $ $300 nm) have been deposited using thermal evaporation method, which undergo transition to crystalline phase under vacuum annealing at 250 $ ^{} $C. Ultrafast transient absorption studies suggest that charge carrier dynamics is dominated by the presence of inter band gap defect states in both films and found to be slower in amorphous as compared to crystalline material due to presence of deeper defect states in amorphous materials. The carrier dynamics of amorphous film is comparably faster at 5 K than 300 K, as the probability of free carriers getting trapped in the defect states is much higher at higher temperature due to their higher mobility. The change in resistance under light and with temperature has been directly correlated with ultrafast spectroscopic data.

中文翻译：

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非晶和结晶In2Se3th薄膜中与温度有关的陷阱辅助超快载流子动力学

陷阱态的存在在光电器件的性能中起着重要作用。在本研究中，新合成的非晶和晶体In $ {2}的电荷载流子动力学$\mathrm{小号}Ë$ {3} $薄膜是使用宽带飞秒泵浦探针光谱法在5-300 K的温度范围内进行的。非晶In $ {2}$\mathrm{小号}Ë$ {3} $薄膜（厚度为$ 300 nm）已使用热蒸发方法沉积，并在250°C的真空退火下经历了转变为结晶相的过程。超快速瞬态吸收研究表明，电荷载流子动力学受两个膜中带隙间隙缺陷状态的影响，并且由于非晶材料中存在更深的缺陷状态，因此与晶体材料相比，非晶态中的载流子动力学较慢。在5 K时，非晶膜的载流子动力学比300 K快得多，这是因为由于较高的迁移率，自由载流子在较高的温度下陷于缺陷状态的可能性要高得多。光照和温度下电阻的变化与超快光谱数据直接相关。