ALL-OPTICAL SILICON-BASED INTEGRATED FIBER-OPTIC MODULATOR, LOGIC GATE, AND SELF-LIMITER

We describe an all-optical mode cutoff modulator for use in fiber optics systems working at wavelengths in the 1.3-1.6μm range. The active waveguide is silicon grown by molecular beam epitaxy, and the channels are fabricated by conventional lithographic techniques and used with standard single-mode fibers. Subnanosecond initiation and recovery times are achieved with less than 150 pJ control energy in a three-port geometry suitable for use as a logic gate. We also present preliminary results when the guided lights is near the bandgap energy and demonstrate self-limiting for integrating Kerr-like self-defocussing nonlinearities. In both cases, the operation of the device is largely wavelength independent and stable.