The nonlinear susceptibility is a measure of a material's nonlinear response to an applied electric field. It determines the strength of the nonlinear effects and is related to the crystal's symmetry ...

Planar optical elements incorporating space-varying Pancharatnam-Berry phase have revolutionized the manipulation of light fields by enabling continuous control over amplitude, phase, and polarization ...

Integrated nonlinear optical devices play an important role in modern optical communications; however, conventional on-chip optical devices with homogeneous or periodic translation dimensions ...