  High-energy tens (10s) to hundreds (100s) petawatt (PW) lasers are key tools
for exploring frontier fundamental researches such as strong-field quantum
electrodynamics (QED), and the generation of positron-electron pair from
vacuum. Recently, pulse compressor became the main obstacle on achieving higher
peak power due to the limitation of damage threshold and size of diffraction
gratings. Here, we propose a feasible multistep pulse compressor (MPC) to
increase the maximum bearable input and output pulse energies through modifying
their spatiotemporal properties. Typically, the new MPC including a prism pair
for pre-compression, a four-grating compressor (FGC) for main compression, and
a spatiotemporal focusing based self-compressor for post-compression. The prism
pair can induce spatial dispersion to smooth and enlarge the laser beam, which
increase the maximum input and output pulse energies. As a result, as high as
100 PW laser with single beam or more than 150 PW through combining two beams
can be obtained by using MPC and current available optics. This new optical
design will simplify the compressor, improve the stability, and save expensive
gratings/optics simultaneously. Together with the multi-beam tiled-aperture
combining method, the tiled-grating method, larger gratings, or negative chirp
pulse based self-compression method, several 100s PW laser beam is expected to
be obtained by using this MPC method in the future, which will further extend
the ultra-intense laser physics research fields.
