Coherence synthesis in nonlinear optics can be actively shaped and controlled without the use of high-power lasers

https://www.eurekalert.org/news-releases/1079090

"coherence not merely byproduct of light sources... periodically poled nonlinear photonic crystals: (1) transfer spatial coherence patterns from IR to visible light through 2nd-harmonic generation, for IR imaging (medical, environmental, security), (2) generate structured light beams (Airy, incoherent vortex, retaining their self-acceleration and orbital angular momentum conservation, respectively), for optical trapping, secure communication, biomedical imaging, (3) modulate speckle fields encoding spatial coherence patterns"