Department of Physics, Indian Institute of Science Education and Research, Bhopal 462023, India.
Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701-2979, USA.
Sci Rep. 2014 Jan 14;4:3686. doi: 10.1038/srep03686.
In this paper, we show for the first time that ultrafast light illumination can induce an unusually broad transient optical absorption (TA), spanning of ≈ 200 nm in the sub-bandgap region of chalcogenide GeSe2 thin films, which we interpret as being a manifestation of creation and annihilation of light induced defects. Further, TA in ultrashort time scales show a maximum at longer wavelength, however blue shifts as time evolves, which provides the first direct evidence of the multiple decay mechanisms of these defects. Detailed global analysis of the kinetic data clearly demonstrates that two and three decay constants are required to quantitatively model the experimental data at ps and ns respectively.
本文首次表明，超快光照射可以诱导出异常宽的瞬态光吸收（TA），在 chalcogenide GeSe2 薄膜的亚带隙区域内跨越约 200nm，我们将其解释为光致缺陷的产生和湮灭的表现。此外，在超快时间尺度下的 TA 在较长波长处出现最大值，但随着时间的演变而蓝移，这为这些缺陷的多种衰减机制提供了第一个直接证据。对动力学数据的详细全局分析清楚地表明，需要两个和三个衰减常数分别在 ps 和 ns 范围内对实验数据进行定量建模。
