High repetition rate supercontinuum generation in undoped KGW and YVO4 crystals

Abstract

We present a comparative experimental study of supercontinuum generation in undoped KGW and YVO4 crystals pumped with near-IR femtosecond laser pulses. We demonstrate that KGW and YVO4 crystals, compared to commonly used sapphire and YAG, have significantly lower supercontinuum generation thresholds, produce remarkably larger red-shifted spectral broadenings and exhibit durable damage-free long-term operation at 2 MHz and 76 MHz repetition rates. Our results show that KGW and YVO4 crystals are excellent nonlinear materials for high repetition rate infrared supercontinuum generation which could be used for the design of high average power optical parametric amplifiers as well as for the development of ultrafast ultrafast spectroscopic and high-speed imaging systems.