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arXiv · 0902.2044

Laser-induced optical changes in amorphous multilayers

M. Malyovanik·S. Ivan·A. Csik·G. A. Langer·D. L. Beke·S. Kokenyesi
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Abstract

It is shown that the well-known blue-shift of the fundamental absorption edge in as-deposited compositionally modulated amorphous Si/Ge and As6Se94/Se80Te20 multilayers (with periods of 4-8 nm) is further enhanced due to the thermal or laser-induced intermixing of adjacent layers. The laser-induced intermixing process, as supported by experiments and model calculations, can be attributed to both the local heating and photo-effects in As6Se94/Se80Te20 multilayers, while only the thermal effects were observed for Si/Ge multilayers. Structural transformations, based on this enhanced interdiffusion, provides good capability for spatially patterning optoelectronic devices and digital information recording.

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M. Malyovanik, S. Ivan, A. Csik, G. A. Langer, D. L. Beke, S. Kokenyesi. 2009-02-12. Laser-induced optical changes in amorphous multilayers. https://doi.org/10.1063/1.1526157

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