featured publications – First steps have been made towards a new light source for ultra-broadband laser pulses in the mid-IR spectral range. A high-power (200 W, 2 mJ) nonlinear thin-disk amplifier serves as a source for 200 fs pulses which are subsequently broadened and compressed to 40 fs in a multi-pass gas cell using the nonlinear effect of self-phase modulation (SPM). The last stage of pulse shortening consists of a high-power argon-filled hollow-core fiber, which has been added to the system recently and is now able to produce a spectral bandwidth of more than 200 nm supporting pulse durations of less than 10 fs. Subsequent conversion of these pulses to the mid-IR using difference frequency generation (DFG) will allow for CEP-stable pulses for attosecond pulse generation.
Image descr.: High-power hollow-core fiber in operation