Ultraviolet laser emission at 355 nm has been demonstrated using a compact assembly of 3%Nd:YVO₄, KNbO₃, BBO and undoped YAG crystal etalons. The single crystal etalons are polished and optically contact bonded together with precise crystallographic alignment. Thin film coatings with high reflectivity at 1064 and 532 nm and with high transmission at 808 and 355 nm are deposited on the exterior surfaces of the crystal assembly. The generation of 355 nm laser light is achieved using BBO cut for critically phase matched, Type II sum frequency mixing of 1064 and 532 nm laser light at room temperature. The 1064 nm laser emission from Nd:YVO₄ is optimally converted to 532 nm using KNbO₃ cut for Type I, critically phase matched SHG at room temperature. This results in mutually orthogonal, highly polarized 1064 and 532 nm laser light, suitable for efficient Type II conversion to 355 nm in BBO. The water sensitive BBO polished surfaces are wholly protected on both sides with undoped YAG. Over 200 (mu) W CW of 355 nm laser light was obtained using a 1 watt 808 nm pump diode. Additional experiments were performed with devices comprised of KTP and BBO for comparison. UV output power was increased through metallization which improves thermal management of the devices. Composite assembly architecture and operational characteristics are reviewed.

Date Published: 26 May 1999
PDF: 3 pages
Proc. SPIE 3610, Laser Material Crystal Growth and Nonlinear Materials and Devices, (26 May 1999); doi: 10.1117/12.349219

Published in SPIE Proceedings Vol. 3610:
Laser Material Crystal Growth and Nonlinear Materials and Devices
Kathleen I. Schaffers; Lawrence E. Myers, Editor(s)