Thin crystal, room-temperature Cr(4+):forsterite laser using near-infrared pumping

We describe a new design for chromium-doped forsterite lasers based on near-IR (700-800-nm) pumping of a thin (3-mm) crystal. In contrast with pumping at 1.06 microm, near-IR pumping permits the use of shorter crystal lengths, which enable one to develop compact and diode-pumped laser geometries. Near-IR pumping also results in an increased effective figure of merit and tuning performance. Using a Ti:Al(2)O(3) pump laser, we investigated cw laser characteristics over a range of pump wavelengths compatible with diode pumping. Room-temperature cw operation with a tuning range of 1175 to 1375 nm was achieved. Kerr-lens mode-locked operation of this laser was also demonstrated with pulse durations of ~50 fs.