Light-induced transmittance oscillation in GeSe2 thin films

Abstract The light-induced light transmittance oscillation observed in GeSe2 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 GeSe2 leading to successive cooling (crystallization) and heating (melting) cycles if the rate of energy absorption and loss are close to equilibrium.