Ultrafast all-optical switching with an asymmetric Fabry-Perot device using low-temperature-grown GaAs: Material and device issues

For future telecommunications systems to take full advantage of the optical fiber bandwidth, it will be necessary to have components responding at pic osecond speeds. The only way currently known to achieve these speeds is usi ng all-optical switching. By using low-temperature-grown GaAs (LT-GaAs) in a compact asymmetric Fabry-Perot device, we have achieved ultrafast all-opt ical switching with large bandwidth, high contrast ratio, low insertion los s, and low switching energy, In this paper, we discuss the dependence of th e switch performance on the mirror bandwidth and reflectivity, and the LT-G aAs layer thickness and growth conditions. We develop guidelines for the op timization of the device design to maximize the bandwidth and contrast rati o.