Av. Rode et al., Dynamics of light-induced reflectivity switching in gallium films deposited on silica by pulsed laser ablation, OPTICS LETT, 26(7), 2001, pp. 441-443
We present what is to our knowledge the first experimental study of light-i
nduced reflectivity changes at an alpha -Ga/Si interface irradiated by femt
osecond and picosecond laser pulses. After exposure, the reflectivity can i
ncrease from R congruent to .0.55, which is typical for alpha -Ga, to R con
gruent to 0.8, which is close to that of liquid Ga. The initial step in the
reflectivity change of 2-4 ps is resolved with 150-fs laser pulses. The li
ght-induced reflectivity change relaxes during 100 ns-10 mus, depending str
ongly on the background temperature of the Ga mirror and the laser fluence.
(C) 2001 Optical Society of America.