High Power DUV Laser for Bright High Harmonic Generation in Gas

Traditionally, brighter high harmonic generation (HHG) is achieved through continuously shifting driving laser to longer wavelength for higher ponderomotive energy and better phase matching. However, such approach has become less effective recently due to the challenge on generating high power MIR laser and the decreasing of HHG energy conversion efficiency. A novel study shows that DUV laser may be an alternative and more sustainable candidate for bright HHG. Intense DUV laser is used to generate effective phase-matching in multiply ionized plasmas, which require high average power, high pulse energy and ultrashort pulse duration simultaneously. This work presents the experimental development progress in our lab on high power DUV laser at 258 nm produced from ps Yb: YAG laser and ionization-induced self-compression of GW ultrashort pulses to tens of fs in gas. Furthermore, combining above two techniques and generating bright high harmonics in capillary filled with noble gas will be discussed.