Pulse Retiming for Improved Switching Rates in Low-Noise Cross-Phase-Modulation-Based Fiber Switches

Temporal multiplexing or demultiplexing of quantum signals would benefit from low-loss, high speed, high rate, and low noise switches. Fiber cross-phase-modulation based switches are a promising solution, but their maximum switching rate is usually limited by pump power limitations. We demonstrate the use of mid-stage pump-pulse re-timing to improve the pump-power efficiency and thus increase the maximum switching rates of such devices. The maximum average pump pulse rate of the switch is shown to increase by more than 50% to 800 MHz when employing pump-pulse retiming. We furthermore confirm the suitability of the switch for quantum signals by sending one of a pair of quantum-correlated photons through the switch while incurring no noticeable degradation of correlations.