The OPCPA technology created at IAP RAS laid down the foundations of the Russian project XCELS intended for construction of the Exawatt Center for Extreme Light Studies. The project was one of the six mega-science projects to be implemented by the end of the current decade approved by the RF Government Committee on High Technologies and Innovations in 2011.

Alexander Sergeev, Corresponding member of RAS, and Gerard Mourou, foreign member of RAS, Chairman of the International Advisory Committee of the XCELS project

A 12-channel laser complex with a total peak power up to 200 PW will be a source of extreme light in XCELS. Each channel is constructed by a common scheme of multicascade parametric amplification, the prototype of which is PEARL. Optical pulses in the channels will be phased to an accuracy much less than the period of a light wave, thereby providing the intensity of light at focusing over 10²⁵ W/cm².
For achieving pulse power exceeding 15 PW in each channel, a pulse with an energy up to 400 J and duration of about 25 fs is generated with repetition rate of 1 shot per several hours. The aperture of the terminal cascades of parametric amplification in DKDP crystals is 30 × 30 cm. Each channel of parametric amplification is pumped by the second harmonic of an Nd:glass laser amplifier with an aperture of 30 × 30 cm. The energy of the fundamental radiation and second harmonic radiation for the pulse duration of 1.5 ns is 3 and 2 kJ, respectively.
The total radiation power of 200 PW surpasses the present day world record by more than two orders of magnitude. This fact will provide superiority of the created facility and scientific and technological leadership of Russia not only at the time of its construction, but also for many years ahead and will enable implementing a unique research program in the following areas:
• creating sources of ultrashort coherent and incoherent radiation with record brightness in the range of X-ray and gamma radiation on the basis of ultrarelativistic particles moving in ultraintense fields and their use for diagnosing processes and structures with picometer spatial and subfemtosecond temporal resolution;
• developing multicascade compact laser accelerators of electrons with energies above 100 GeV, developing promising accelerator complexes with particle energies of 1—10 TeV using the principles of laser-plasma acceleration;
• creating compact laser accelerators of ions with energies of 0.1—10 GeV and developing their applications for radiation diagnostics and medicine;
• producing and studying extreme states of matter arising under the influence of ultrarelativistic laser fields, modeling of astrophysical and early cosmological phenomena in laboratory conditions;
• creating sources of electromagnetic waves of attosecond (10^—18 s) and subattosecond duration based on generation of high harmonics of laser radiation and supercontinuum in the course of nonlinear interaction of intense femtosecond laser pulses with matter, developing methods of fundamental metrology and diagnostics of ultrafast processes based on such sources;
• creating a source of electromagnetic radiation with a peak power of more than 1 EW (10¹⁸ W) based on the interaction of multipetawatt laser pulses with plasma in the ultrarelativistic regime;
• studying the space-time structure of vacuum probed by the radiation with an intensity of more than 10²⁵ W/cm², studying the phenomena of quantum electrodynamics in ultraintense laser fields, including producing matter and antimatter by means of radiation;
• research in the new field of science — nuclear optics — based on the use of secondary sources of gamma radiation for excitation and diagnostics of intranuclear processes.