High peak power passive Q-switched widely tunable Tm:YAP laser

This paper presents a novel, widely tunable, passively Q-switched Tm:YAP laser operating at high peak power in the 2-micron spectral range. While widely tunable lasers typically operate in continuous wave (CW) mode, and customary high peak power designs rely on active Q-switching methods, our innovative design combines both features in an all-passive configuration. The continuous tunability spectrum spans 41 nm, from 1911 nm to 1952 nm. Wavelength tunability was achieved using a 25 mu m thick YAG etalon. A Cr:ZnS saturable absorber is used for passive Q-switching, achieving a maximal repetition rate of 3 kHz, maximal energy per pulse of 1.42 mJ, and a very high maximum peak power of 54 kW. Additionally, a detailed theoretical analysis of the energy dependency on the wavelength is discussed. Such laser properties, especially implemented in an all-passive configuration, have great application prospects in many fields.