U4+:SrF2 efficient saturable absorber <i>Q</i> switch for the 1.54 μm erbium:glass laser

Abstract

Saturable absorber Q switching of the Er:glass laser at 1533 nm using U4+:SrF2 has been obtained. Q-switched pulses of 3 mJ and 60 ns full width at half-maximum were achieved using a 2.69-mm-thick Q switch in a 14-cm-long plane-parallel cavity, with a 3×50 mm Kigre QE-7S Er:glass rod. The high absorption cross section of U4+:SrF2 resulted in efficient Q-switched operation (without intracavity focusing) in agreement with the theoretical predictions.