A. E. Kaplan

Reflection of a Gaussian beam at a nonlinear interface

By numerical simulations of the reflection of a (2-D) Gaussian beam from a nonlinear interface, we show several new features of the behavior of such an interface and resolve the difference between the results of two previous studies of this type. Newly reported features include a very large nonlinear Goos-Hanchen shift and large variations of the angle of an output beam for small changes in the input intensity. The latter phenomenon has potential applications for a light-controlled angular scanning element. The differences between prior studies of this type are shown to be an artifact of the numerical procedures used.

Enhancement of the Sagnac effect due to nonlinearly induced nonreciprocity.

We propose a novel way to enhance the Sagnac effect by using a nonlinear ring interferometer. Specifically, we take advantage of the nonlinearly induced nonreciprocity of counterpropagating waves caused by the formation of an index grating in the nonlinear medium.

Direct measurement of the transverse velocity of dark spatial solitons

We describe the direct experimental measurement of the transverse propagation velocities of dark spatial solitons. Good agreement is obtained from a comparison of the velocities measured experimentally and the velocities predicted by the two-dimensional theory of Zakharov and Shabat [Sov. Phys. JETP 37, 823 (1973)].

Directionally asymmetrical bistability in a symmetrically pumped nonlinear ring interferometer

Abstract We consider a nonlinear ring resonator pumped symmetrically by two beams of equal intensities and opposite directions. We show that this system is characterized by a new directionally asymmetrical regime of multistability. This is due to the non-reciprocity of propagation of the counterpropagating waves in the resonator produced by a nonlinear index grating.

An internet accessible telepresence

Abstract.The US Vice President, Al Gore, in a speech on the information superhighway, suggested that it could be used to remotely control a nuclear reactor. We do not have enough confidence in computer software, hardware, or networks to attempt this experiment, but have instead built a Internet-accessible, remote-controlled model car that provides a race drivers view via a video camera mounted on the model car. The remote user can see live video from the car, and, using a mouse, control the speed and direction of the car. The challenge was to build a car that could be controlled by novice users in narrow corridors, and that would work not only with the full motion video that the car natively provides, but also with the limited size and frame rate video available over the Internet multicast backbone. We have built a car that has been driven from a site 50 miles away over a 56-kbps IP link using

Research on nonlinear optical materials: an assessment

\mbox{{\tt nv}}

Light-induced nonreciprocity, field invariants, and nonlinear eigenpolarizations

format video at as little as one frame per second and at as low as

Optical bistability that is due to mutual self-action of counterpropagating beams of light

100\times 100

Xunet 2: a nationwide testbed in high-speed networking

pixels resolution. We also built hardware to control the car, using a slightly modified voice grade channel videophone. Our experience leads us to believe that it is now possible to put together readily available hardware and software components to build a cheap and effective telepresence.

Positron and gamma-photon production and nuclear reactions in cascade processes initiated by a sub-terawatt femtosecond laser

The seven papers making up this assessment are based on the Workshop on Nonlinear Optical Materials held in April 1986.