Realization of compact Watt-level single-frequency continuous-wave self-tuning titanium: sapphire laser.

Here, we present a compact Watt-level single-frequency continuous-wave (CW) self-tuning titanium:sapphire (Ti:S) laser, which is implemented using a three-plate Ti:S crystal as both a gain medium and frequency-tuning element. The thickness ratio of the three-plate Ti:S crystal is 1:2:4, of which the thinnest plate measured 1 mm. The optical axes lie on their own surfaces and parallel to each other. Based on the presented self-tuning crystal, a ring resonator is designed and built. The maximum wavelength tuning range of the single-frequency self-tuning Ti:S laser is 108.84 nm, as demonstrated experimentally by rotating the three-plate Ti:S crystal, indicating good agreement with theoretical prediction. To the best of our knowledge, this is the first study to report a single-frequency CW self-tuning Ti:S laser, which can provide a feasible approach for achieving a compact all-solid-state single-frequency CW-tunable Ti:S laser.