Abstract

The development of ultrafast optical sources in the ultraviolet (UV) is of interest for variety of applications from quantum optics to biology. With the scarcity of solid-state lasers in the UV, nonlinear frequency conversion techniques represent a promising route for the generation of such source. In particular, intracavity frequency doubling of optical parametric oscillators (OPO) synchronously-pumped in the green can be an attractive approach to generate tunable high-repetition-rate ultrashort pulses in the UV. However, development of OPOs based on the well-established quasi-phase-matched nonlinear materials such as PPLN is challenging, when pumped in the green, due to photorefractive effect. On the other hand, MgO:sPPLT has proved to be an attractive alternative for green pumping [1]. At the same time, the birefringent nonlinear material, bismuth triborate, BiB₃O₆ (BIBO), possesses unique nonlinear optical properties for frequency conversion from the UV to IR [2]. It offers a relatively high nonlinearity (d_eff~3.2 pm/V) as compared to other widely used borate-based crystals such as LBO and BBO, making it an excellent nonlinear material for UV generation. Thus, the combination of green-synchronously-pumped OPO based on MgO:sPPLT together with internal frequency conversion in BIBO represents a versatile and practical approach to the development of tunable ultrafast sources in the UV.

© 2013 IEEE