Giant broadband refraction and nonlinear optics in ferroelectric super-crystals

Eugenio Delre
Dipartimento di Fisica, Università di Roma La Sapienza, 00185 Rome, Italy
We review recent progress in the study of linear and nonlinear propagation in ferroelectric super-crystals. The three-dimensional super-lattice of spontaneous polarization vortices leads to giant broadband refraction across the entire visible spectrum. Absence of diffraction, chromatic dispersion, and propagation normal to the crystal facets is compatible with giant values of index of refraction larger that 25. The huge values of optical susceptibility greatly enhance second-harmonic generation efficiency with broadband spectral and angular acceptance.