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Nanosecond dynamics of a gallium mirror's light-induced reflectivity change

V. Albanis·S. Dhanjal·V. I. Emelyanov·V. A. Fedotov·K. F. MacDonald·P. Petropoulos·D. J. Richardson·N. I. Zheludev
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Abstract

Transient pump-probe optical reflectivity measurements of the nano/microsecond dynamics of a fully reversible, light-induced, surface-assisted metallization of gallium interfaced with silica are reported. The metallization leads to a considerable increase in the interface's reflectivity when solid a-gallium is on the verge of melting. The reflectivity change was found to be a cumulative effect that grows with light intensity and pulse duration. The reflectivity relaxes back to that of alpha-gallium when the excitation is withdrawn in a time that increases critically at gallium's melting point. The effect is attributed to a non-thermal light-induced structural phase transition.

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V. Albanis, S. Dhanjal, V. I. Emelyanov, V. A. Fedotov, K. F. MacDonald, P. Petropoulos, D. J. Richardson, N. I. Zheludev. 2000-10-05. Nanosecond dynamics of a gallium mirror's light-induced reflectivity change. https://doi.org/10.1103/physrevb.63.165207

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