title: Nanosecond light induced, thermally tunable transient dual absorption bands in a-Ge₅As₃₀Se₆₅ thin film.
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.
authors.affiliation: Department of Physics, Indian Institute of Science Education and Research, Bhopal 462023, India.
authors.forename: Pritam
authors.initials: P
authors.lastname: Khan
authors.affiliation: Department of Physics, Indian Institute of Science Education and Research, Bhopal 462023, India.
authors.forename: Tarun
authors.initials: T
authors.lastname: Saxena
authors.affiliation: Department of Materials Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
authors.forename: H
authors.initials: H
authors.lastname: Jain
authors.affiliation: Department of Physics, Indian Institute of Science Education and Research, Bhopal 462023, India.
authors.forename: K V
authors.initials: KV
authors.lastname: Adarsh