Femtosecond Laser-Induced Disorder of the (1 3 1)-Relaxed GaAs(110) Surface
نویسندگان
چکیده
Surface physical changes (disorder and/or damage) due to femtosecond pulsed laser irradiation are observed in a new regime of extremely low laser fluence (,1023 of the single shot damage fluence) and large number of laser shots (.1010). No bulk damage was detected. The surface disorder is reversible by thermal annealing at 580 ±C. We propose a new mechanism for femtosecond laser-induced surface physical reactions. Disorder is caused by a surface dangling bond hole-induced lattice instability which lowers the barrier to disorder to the order of kBT . This occurs during high density local fluctuations even though the mean hole density is far lower than that needed for global instability.
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