Focusability of femtosecond laser pulses after nonlinear post-compression

The nonlinear nature of laser pulse post-compression inevitably leads to wavefront distortions. These distortions are nonstationary, i.e., they vary during the pulse, which significantly complicates the use of adaptive optics. We propose four approaches to compensation of wavefront distortions by means of standard adaptive mirrors, three of which can be implemented experimentally. Numerical simulations show that these approaches allow achieving a focal spot intensity close to the case of a perfectly flat wavefront.