Tunable filters for precise spectral gain control in ultra-short-pulse laser systems

Opt Lett. 2016 Oct 15;41(20):4708-4711. doi: 10.1364/OL.41.004708.

Abstract

We present tunable spectral filters (TSFs) as a variable and precisely adjustable method to control the spectral gain of short-pulse laser systems. The TSFs provide a small residual spectral phase and a high damage threshold, and generate no pre- or post-pulses. The method is demonstrated for two different laser materials and can be applied as an intracavity compensation in regenerative amplifiers as well as a method for pre-compensation in high-energy multipass amplifiers. With this method, a full width at half-maximum bandwidth of 23.9 nm could be demonstrated in a diode-pumped, 50 J Yb:CaF2 amplifier.