Search

Using achromatic gratings techniques we have written dynamic holograms on an optically addressed spatial light modulator with a temporally and spatially incoherent white light source. The resolution and depth-of-field of these holograms are theoretically derived and experimentally verified. We demonstrate writing speeds over an order of magnitude faster than video framing rates.

Beam fanning is examined as a noise source in monochromatic and achromatic two-wave mixing. We show that fanning acts mainly as a parasitic loss for low beam ratios, whereas it contributes a background noise floor for high beam ratios. In the first regime, fanning loss is much smaller in achromatic two-wave mixing than in the monochromatic case.

We show that the gradient force due to counterpropagating light beams can be used to create an experimentally realizable three-dimensional analog of the one-dimensional Frenkel-Kontorova model.

Using nondegenerate two-wave mixing in colloidal suspensions we measure the viscosity of liquids with as little as 20 picoliters of volume. In addition, changes in the frequency signature with intensity are observed which are interpreted in terms of self-focusing effects.

We have studied the nonlinear index of refraction of pink ruby between 565 nm and 610 nm using nondegenerate two-wave mixing at 77 K and 294 K. Our new results support the model originally proposed by Venkatesan and McCall based on the large cross section of the transition from the Kramers doublets to the charge transfer band. In addition, we show that two-wave mixing can be used for accurate determination of the 2 E lifetime under conditions where radiation trapping makes fluorescence decay measurements difficult.

It was known for some time now that gated imaging with short laser pulses is possible in a scattering medium.

We present a set of experiments in which optical fibres are prepared with three optical fields of different frequencies to produce second harmonic generation. The results obtained are shown to be inconsistent with directional photoionisation models for second harmonic generation in glasses.

We present a simple model to predict the linear electro-optic coefficients for a new class of materials based on the inclusion compounds of hydroquinone. The predicted Pockels coefficient for the β-quinol: CH3OH inclusion compound is of the same order as that of KDP.