J. A. Giordmaine

SECOND-HARMONIC GENERATION IN WAVEGUIDES INDUCED BY PHOTOREFRACTIVE SPATIAL SOLITONS

We propose and demonstrate experimentally second-harmonic generation in waveguides induced by photorefractive solitons, and show that the conversion efficiency is improved considerably.

Spatial vector solitons consisting of counterpropagating fields.

We present the experimental observation of a spatial vector soliton formed by counterpropagation of coherent optical fields. This is to our knowledge the first observation of a vector soliton in which the induced waveguide (potential) is periodic in the propagation direction. This vector soliton induces a waveguide and a thick grating within the waveguide, which can be used as a tunable optical waveguide filter.

Optical parametric oscillation in soliton-induced waveguides

We demonstrate experimentally an optical parametric oscillator constructed in a waveguide induced by a photorefractive spatial soliton and show that the pumping threshold is reduced considerably.

Tuning of second-harmonic generation in waveguides induced by photorefractive spatial solitons

We demonstrate experimentally wavelength tuning of second-harmonic generation in waveguides induced by photorefractive solitons in a KNbO3 crystal. By rotating the crystal, we can attain as large wavelength tunability as in bulk but with considerable improvement in conversion efficiency and elimination of walk-off.

All-ultraviolet time-resolved coherent anti-Stokes Raman scattering

We report all-UV coherent anti-Stokes Raman scattering (CARS) in calcite with 250-280 nm pump, Stokes, probe, and anti-Stokes light. UV CARS efficiency is approximately 7x higher than for comparable scattering in the visible, 480-540 nm. Time-resolved UV CARS reveals lengthening of the dephasing time of 1086 cm(-1) CO3(2-) internal vibrations from 4 to 7 ps with increasing vibrational excitation, consistent with a phonon depletion model.

Optical parametric oscillator in waveguides induced by photorefractive spatial solitons

Summary form only given. In an OPO, the threshold pump power is dependent on the signal gain per pass through the crystal. We demonstrate OPOs in waveguides induced by photorefractive solitons, and show that by using waveguiding, the gain is increased, leading to a greatly reduced threshold pump power for the same cavity loss. We build a doubly-resonant oscillator, in which the oscillation occurs at both the signal and the idler wavelengths. At the highest pump power, the output signal is slightly weaker than without the soliton. This is because on the reverse direction the signal and the idler transfer energy back to the pump beam, and the soliton waveguiding improves the efficiency of this reverse process as well. This issue can be readily resolved by use of a singly-resonant or a ring oscillator.

Grating filters in solitoninduced waveguides

We study experimentally the grating formed by two head-on colliding (counter-propagating) (1+1) D photorefractive solitons. Such gratings can be used as tunable waveguide filters in reconfigurable planar lightwave circuits

Tuning of second harmonic generation in soliton-induced waveguides

Summary form only given.We have demonstrated that photorefractive soliton-induced waveguides can improve the SHG conversion efficiency considerably while offering tuning angle range of /spl plusmn/7/spl deg/, which translates into 4 nanometer tunability. We expect much higher improvement with a longer crystal and a narrower soliton.

Second harmonic generation in waveguides induced by photorefractive spatial solitons

We propose and demonstrate experimentally second-harmonic generation in waveguides induced by photorefractive solitons, and show that the conversion efficiency is improved considerably.