Abstract

We describe a simple imaging technique that can be used to photograph ultrafast processes with time resolution determined by the duration of pump and probe laser pulses. We demonstrate this technique by photographs having 100-fsec time resolution of a silicon surface undergoing melting and evaporation following intense excitation by an ultrashort laser pulse. These photographs resolve the increase in surface reflectivity caused by surface melting both temporally and spatially. Material evaporation from the melted surface further alters the image of the surface by absorbing and scattering the illuminating laser light. Our analysis of this selectively imaged light suggests that the evaporated material emerges as liquid droplets several hundred angstroms in diameter, which atomize in less than a nanosecond.

© 1985 Optical Society of America

Femtosecond spectroscopy with high-power tunable optical pulses

A. Migus, A. Antonetti, J. Etchepare, D. Hulin, and A. Orszag
J. Opt. Soc. Am. B 2(4) 584-594 (1985)

Three-pulse scattering for femtosecond dephasing studies: theory and experiment

A. M. Weiner, S. De Silvestri, and E. P. Ippen
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Ultrafast relaxation dynamics of photoexcited carriers in GaAs and related compounds

A. J. Taylor, D. J. Erskine, and C. L. Tang
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Charge emission and precursor accumulation in the multiple-pulse damage regime of silicon

Y. K. Jhee, M. F. Becker, and R. M. Walser
J. Opt. Soc. Am. B 2(10) 1626-1633 (1985)

Second-harmonic and sum-frequency generation in reflection: probing of GaAs surface structure and laser-induced phase transitions

S. A. Akhmanov, N. I. Koroteev, G. A. Paitian, I. L. Shumay, M. F. Galjautdinov, I. B. Khaibullin, and E. I. Shtyrkov
J. Opt. Soc. Am. B 2(2) 283-288 (1985)