DETECTION OF EXCIMER-LASER INDUCED SUB-PICOMETER ULTRASONIC DISPLACEMENT AMPLITUDES

Ultrasonic pulses were generated by low-intensity laser pulses and det ected by optical techniques and by conventional transducers. The one-d imensional model describing the resulting displacement at the sample b ack surface was experimentally confirmed. Ultrasonic displacements wer e detected by a stabilized Michelson interferometer and by a piezoelec tric transducer, simultaneously. The calibration was extrapolated to a n extremely low intensity range where displacements of the order of ma gnitude of 10(-14) m were generated and detected by piezoelectric tran sducers.