Studies of self-focusing bistable devices using liquid suspensions of dielectric particles.

We describe the results of experiments on bistable and multistable self-focusing devices using liquid suspensions of dielectric particles as the nonlinear medium. The nonlinear parameters for this medium are calculable from first principles. A simple model predicts regions of bistability and multistability that are in good agreement with the experimental observations.

Passive mode locking of a semiconductor diode laser.

By using a GaAs/GaAIAs multiple-quantum-well sample as a saturable absorber in an external resonator, we have passively mode locked a GaAs laser to obtain pulses as short as 1.6 psec, the shortest pulses ever observed to our knowledge from a mode-locked diode laser in a regulator pulse train.

Measurement of electronic optical Kerr coefficients.

We describe a degenerate four-wave mixing technique for measuring optical Kerr coefficients. This technique permits discrimination between fast and slow (thermal) nonlinearities. We report results for a number of long-chain organic materials.