Formation of microstructures in As₂S₃by a femtosecond laser pulse train

Irradiation of the As2S3 chalcogenide glass by a train of focused femtosecond laser pulses from a master oscillator based on a Ti:sapphire crystal results in the formation of submicron structures in the bulk of the sample with modified optical properties. The minimum exposure time for producing such microstructures does not exceed 1 mus. A model based on two-photon absorption of laser radiation and local beating of the sample material is proposed for this phenomenon.