Few-cycle 10 µm multi-terawatt pulse self-compression in a gas-filled multi-pass cell: a numerical experiment

A gas-filled multi-pass cell is modeled to self-compress a 10 µm pulse to sub-100 fs duration while containing multi-terawatts of peak power. The motivation for modeling a source with the demonstrated power is for use in laser wakefield accelerators. The cell is filled with the second most abundant isotope of CO₂¹³CO₂, which has a shifted dispersion/absorption relative to the gain medium generating the laser pulse, ¹²CO₂. This allows for low-loss, long-distance propagation in the anomalous group velocity dispersion (GVD) Kerr medium, leading to self-compression of the initially 3.5 ps, 1 TW pulse. The pulse reaches a duration of 300 fs inside the cell before outcoupling through the anomalous GVD NaCl window, causing further compression to 87 fs and containing 8.35 TW peak power. By combining the self-compression of the gas-filled multi-pass cell with a post-compression anomalous GVD element, a hybrid compression scheme has been demonstrated.