High-power, single-frequency Ti:sapphire laser pumped by a continuous-wave fiber laser green source

The titanium-doped sapphire (Ti:Al2O3) laser has been established as the workhorse tunable solid-state laser for the near-infrared spectral range, for continuous-wave (cw) as well as ultrafast timescales, benefiting numerous applications. Ti:sapphire laser have relied mainly on argon ion lasers and frequency-doubled Nd-based green lasers as the pump source [1]. Other possible pumps include optically-pumped-semiconductor-lasers in the green, employing intracavity frequency-doubling and, more recently, GaN diode lasers in the blue, but with limitations of low output power and poor beam quality. Fiber lasers have recently attracted much attention for their compact design, robustness, power scalability with turnkey operation and cost effectiveness. The combination of a cw infrared fiber laser and a simple single-pass second-harmonic-generation scheme based on MgO:sPPLT is a potentially attractive route for high-power cw green generation [2]. Hence, it is worthwhile to explore its potential as a new pump architecture for the Ti:sapphire laser, which would provide a simple, high-power, compact, and cost-effective alternative to the traditional, cw solid-state green sources.