Ultra-compact diode-pumped single-frequency Ti:sapphire laser.

In this Letter, we report on the development of an ultra-compact single-frequency Ti:sapphire laser under direct diode pumping. Single-longitudinal-mode operation is realized from a miniature plane-parallel resonator using a volume Bragg grating as an output coupler. InGaN laser diodes operating at around 470 nm and 490 nm with a combined power of 6.