Nonlinear Dielectric Nanoresonators and Metasurfaces: Toward Efficient Generation of Entangled Photons

Abstract

Among the most prominent effects resulting from nonlinear light–matter interaction is the generation of correlated and entangled photons through various processes, notably via spontaneous parametric down-conversion or spontaneous four-wave mixing. Such nonlinear optical processes benefit from the concentration of electromagnetic fields in small volumes. Dielectric nanoresonators and their 2D layouts—metasurfaces—provide efficient ways to control light in subwavelength volumes enabling the enhancement of nonlinear light–matter interaction and the generation of entangled photons. Nanoresonators and metasurfaces offer a radical miniaturization of quantum light sources allowing better scalability, which opens a pathway toward arrangements of photon sources in complex subwavelength configurations for advanced photon state control. In this work, the recent progress in this emergent area of research is reviewed.