Author(s): J. Stöhr
Conventional diffraction theory is predicted to break down for x-rays when spontaneous scattering is replaced by stimulated scattering by a thin film source. The stimulated diffraction pattern generated by the cooperative interaction of two coherent, unentangled photons results in self-focussing beyond the diffraction limit.
[Phys. Rev. Lett. 118, 024801] Published Wed Jan 11, 2017