Femtosecond pulse stretcher based on a modified Offner triplet

Summary form only given. The generation of sub-30-fs pulses is expected to lead to new applications in many areas including high-order harmonic generation, plasma wakefield excitation, and ultrafast X-ray lasers. However, amplification to high energies of such femtosecond pulses by chirped pulse amplification (CPA) requires high-order dispersion control in the stretching, amplification, and recompression of pulses. A stretcher based on two cylindrical mirrors employing non-normal incidence angles on the mirrors has been demonstrated to eliminate phase distortions up to the fifth order, while a CPA laser system using a stretcher based on an on-axis all-reflective Offner triplet has generated high-contrast compressed pulses. In this paper, we present the design of a new stretcher based on a modified off-axis Offner triplet, which preserves the low aberration qualities of the Offner triplet while allowing cancellation of second-, third-, and fourth-order phase dispersion in a CPA laser system.