Light-induced transmittance oscillation in GeSe2 thin films

Abstract The light-induced light transmittance oscillation observed in GeSe 2 thin films can be maintained only within a certain light intensity range, in our case between 1.4 and 2.7 kW cm -2 . Oscillation frequency and the transmittance change are controlled by energy absorption and loss; they could be varied from 3–50 Hz and ∼ 10–90%, respectively. Oscillation is caused by differences in the absorption coefficients of the melt and the crystalline GeSe 2 leading to successive cooling (crystallization) and heating (melting) cycles if the rate of energy absorption and loss are close to equilibrium.