In this review paper, the results of recent observation and studies of the nonlinear magneto-optical effects in magnetophotonic crystals (MPC) are surveyed. Key point of our interests in nonlinear optics of MPC is extension of nonlinear optical enhancement recently observed in dielectric photonic crystals (PC) to enhancement of intrinsically weak nonlinear magneto-optical effects. These PC mechanisms of strong increase of efficiency of nonlinear optical effects are related to optical field increase due to the light localization and parametric enhancement due to the phase-matching.
Strong magnetization-induced intensity effect in second-harmonic (SHG) and third-harmonic (THG) generation is observed in magnetophotonic microcavities formed from single half-wave magnetic garnet layers, sandwiched between two nonmagnetic dielectric photonic mirrors. Absolute values of magnetization-dependent contributions to the SHG and THG intensity are strongly enhanced due to light localization in microcavity garnet spacer.
Magnetization-induced intensity effects in SHG are observed in two types of MPC: one-dimensional multilayer MPC formed from pairs of alternating quarter-wavelength magnetic garnet and silicon oxide layers and three-dimensional MPC based on synthetic silica opals infiltrated by magnetic garnet. Parametric enhancement of MSHG intensity is due to phase-matching at the bend edge. Pure magnetic component of phase-matched SHG is enhanced by two orders of magnitude in garnet MPC in experimental geometry as nonmagnetic SHG is canceled.
Apart from intensity effects, magnetic impact strongly influences other parameters of the SHG radiation in MPC. Significant magnetization-induced variations of phase and rotation of polarization of the SHG waves are observed and systematically studied in garnet multilayer MPC.