PHASE-SENSITIVE OPTICAL PROBE FOR SURFACE-ACOUSTIC-WAVE SOLITON INVESTIGATION

A novel phase-sensitive optical probe for observation of nonlinear sur face acoustic wave (SAW) has been constructed. The probe operates in t he acoustic pulse mode that allows input powers as high as 20 W. Light from a solid-state laser diode is modulated at frequencies up to 1 GH z that enables a broad-band detection of SAW and its harmonics. Measur ement of harmonic generation has been carried out on LiNbO3 single-cry stal plater, and information on both amplitudes and phases of the harm onics has been obtained. The developed experimental technique provides a foundation for optical detection of the waveform of nonlinear SAW, and is aimed at the observation of SAW solitons.