Single Cycle Thin Film Compressor Opening the door to   Zeptosecond-Exawatt Physics
  This article demonstrates a new compression scheme that has the potential to compress a high energy pulse as high as a few hundred Joules in a pulse as short as one optical cycle at 0.8{\mu}m making a true ultra-relativistic {\lambda}^3 pulse. This pulse could have a focused intensity of 10^24W/cm2 or a0 of 1000. It could form an efficient, 10%, relativistic mirror that could compress the pulse to the atto-zeptosecond regime, with an upshifted wavelength of 1-10keV. This technique could be a watershed making the entry of petawatt pulses into the exawatt and zeptosecond regime possible. 
G. Mourou, S. Mironov, E. Khazanov, A. Sergeev
physics.optics