High-efficiency KYW acousto-optic Q-switch for a Ho:YAG laser
Alexander I. Chizhikov, Aleksey V. Mukhin, Nikolay A. Egorov, Vasily V. Gurov, Vladimir Y. Molchanov, Natalya F. Naumenko, Konstantin V. Vorontsov, Konstantin B. Yushkov, Nikita G. Zakharov
Abstract
A new, to the best of our knowledge, type of acousto-optic Q -switch was developed using slow shear acoustic mode in potassium yttrium tungstate (KYW) crystal. Two Q -switch configurations were created: one for vertical and one for horizontal light polarization, both providing over 50% diffraction efficiency at a wavelength of 2.1 μm and an RF driving power below 8 W. The laser-induced damage threshold of the KYW crystal was found to equal 650 MW/cm 2 . Operation of a nanosecond periodically pulsed Ho:YAG laser emitting 15 mJ pulses at 2.1 μm with the KYW Q -switch is reported.