Compact and ultra-high contrast nonlinear temporal filter for PW and 10 PW-level Ti:sapphire laser facilities

A compact nonlinear temporal filter with ultra-high temporal contrast is reported in this work. Adopting the idler pulses generated by the nonlinear temporal filter, which combines with the cross-polarized wave generation (XPWG) and the cascaded femtosecond optical parametric amplification (CF-OPA), the experimental measurement with limited dynamic range has already revealed a capability of more than 8 orders of magnitude on the temporal contrast enhancement. This is much higher than the commonly used nonlinear temporal filter ever reported. Meanwhile, more than 100 µJ energy and over 150 nm full spectrum width can be obtained for the idler pulses. Due to the high gain of the CF-OPA, the output energy of XPWG can be kept as low as 1 µJ, which is helpful to reduce the total optical path and hence facilitates the miniaturization of the device. The nonlinear pulse filter now occupies only 0.85m×0.6m, less than half the size of the original ones. The compactness and ultra-high temporal contrast of the nonlinear pulse filter make it an excellent seed source for PW and 10 PW-level laser facilities.