Multistability and chaos in a semiconductor microwave device with time-delay feedback

We propose a tunable microwave device consisting of a Gunn diode with time-delay feedback, which will emit chaotic microwaves. The wavelength is controlled by two incident laser beams which trigger moving multiple Gunn domains. Predicted phenomena include the coexistence of stationary and chaotic states, complicated hysteresis loops, and persistent bistabiliy. This device is potentially useful for applications such as secure microwave communications, memory devices and those involving photorefractive effects.