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arXiv · 1405.0890

Nanosecond light induced, thermally tunable transient dual absorption bands in a-Ge5As30Se65 thin film

Pritam Khan·Tarun Saxena·K. V. Adarsh
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Abstract

In this article, we report the first observation of nanosecond laser induced transient dual absorption bands, one in the bandgap (TA1) and another in the sub-bandgap (TA2) regions of a-Ge5As30Se65 thin films. Strikingly, these bands are thermally tunable and exhibit a unique contrasting characteristic: the magnitude of TA1 decreases while that of TA2 increases with increasing temperature. Further, the decay kinetics of these bands is strongly influenced by the temperature, which signifies a strong temperature-dependent exciton recombination mechanism. The induced absorption shows quadratic and the decay time constant shows linear dependence on the laser beam fluence.

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Pritam Khan, Tarun Saxena, K. V. Adarsh. 2014-05-05. Nanosecond light induced, thermally tunable transient dual absorption bands in a-Ge5As30Se65 thin film. https://doi.org/10.1038/srep06573

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