Coherent light sources providing sub‐wavelength confined modes are in ever more demand
to face new challenges in a variety of disciplines. Scalability and cost‐effective production of …

High-quality crystals without inversion symmetry are the conventional platform to achieve
optical frequency conversion via three-wave mixing. In bulk crystals, efficient wave mixing …

Nonlinear response in a material increases with its index of refraction as n 4. Commonly, n~
1 so that diffraction, dispersion, and chromatic walk-off limit nonlinear scattering …

We investigate systematically the evolution of second harmonic generation in strontium
barium niobate with different degrees of disorder of its χ^ 2 nonlinearity. These different …

We analyze the conical second-harmonic generation via Čerenkov-type phase matching in
two-dimensional decagonal nonlinear photonic quasi-crystals for linear, circular, and …

We investigate experimentally and theoretically the conical emission of Čerenkov-type third-
harmonic generation in strontium barium niobate of random 2D-χ (2) distribution. The …

We report on experimental and theoretical studies of Čerenkov-type second-harmonic
generation in random nonlinear photonic structures with different two-dimensional …

From the appearance of the laser, 50years ago, the use of ferroelectric crystals in optical
devices has constituted a field of much interest and activity. Ferroelectric materials have …

In experiments on second harmonic (SH) generation (SHG), a conical structure of radiation
has been observed. In the present study, a non-stationary theory of SH excitation of …

We demonstrate the application of as-grown calcium barium niobate (CBN) crystal with
random-sized ferroelectric domains as a broadband frequency converter. The frequency …