PHz scale spectral broadening and few-cycle compression of Yb:KGW laser pulses in a pressurized, gas-filled hollow-core fiber

Abstract: We demonstrate efficient generation of coherent super-octave pulses via a single-stage spectral broadening of a Yb:KGW laser in a single, pressurized, Ne-filled, hollow-core fiber capillary. Emerging pulses spectrally spanning over more than $\sim$1 PHz (250 nm- 1600 nm) at a dynamic range of $\sim$60 dB, and an excellent beam quality open the door to combining Yb:KGW lasers with modern light field synthesis techniques. Compression of a fraction of the generated supercontinuum to intense (8 fs, $\sim$2.4 cycle, $\sim$650 $\mu$J) pulses allows convenient use of these novel laser sources in strong-field physics and attosecond science.