this disclosure demonstrates successfully using single , polycrystalline , hot pressed ceramic , and thin film fe doped binary chalcogenides as saturable absorbing passive q - switches . the method of producing polycrystalline znse yields fairly uniform distribution of dopant , large coefficients of absorption and low passive losses while being highly cost effective and easy to reproduce . using these fe 2 + : znse crystals , stable q - switched output was achieved with a low threshold and the best cavity configuration yielded 13 mj / pulse single mode q - switched output and 85 mj in a multipulse regime .