Second harmonic generation: applications in phase diagram investigations

Voltage-controlled phase matching in quadrupole second-harmonic generation.

We have observed strong phase-matched (PM) quadrupole optical second-harmonic generation (SHG) from nematic liquid crystals that possess inversion symmetry. PM conditions were achieved for two configurations by voltage control of the molecular orientation and thus of the refractive indices. Quadrupole SHG was separated from electric-field-induced dipole-type SHG with the help of time-gated meas...

Phase-Locked Second Harmonic Generation in GaAs nanocavities

We theoretically study light propagation through sub-wavelength apertures on a silver substrate filled with GaAs, in the enhanced transmission regime. We predict enhanced conversion efficiencies even under high absorption conditions. ©2010 Optical Society of America OCIS codes: (240.6680) Surface Plasmon, (120.7000) Transmission, (240.3695) Linear and nonlinear light scattering from surfaces, (...

Atomically phase-matched second-harmonic generation in a 2D crystal

Second-harmonic generation (SHG) has found extensive applications from hand-held laser pointers to spectroscopic and microscopic techniques. Recently, some cleavable van der Waals (vdW) crystals have shown SHG arising from a single atomic layer, where the SH light elucidated important information such as the grain boundaries and electronic structure in these ultra-thin materials. However, despi...

Second-harmonic generation

The goal of this experiment in nonlinear optics is to study the conversion of a (very small) fraction of laser light from its original wavelength of 980 nm (i.e. invisible to the naked eye) to its second-harmonic at a wavelength of 490 nm. This conversion takes place by mild focussing of an intense laser beam in a nonlinear birefringent crystal of BBO (= β BaBO4). You will study the physical pr...

Collinear phase matching for second harmonic generation using conoscopic interferometry