Speaker
Description
Emerging applications of X-ray free-electron lasers would benefit from femtosecond (fs) pulse durations and fs timing accuracies. The latter requires synchronization that can simultaneously lock all components with a precision better than the accelerator pulse duration. Large-scale facilities are usually synchronized using an RF reference clock and electronic phase-locking techniques. With this approach, it is only possible to synchronize pulses with about 100 fs resolution. To improve long-range synchronization the all-optical links with pulsed optical signals are used. Recently, bunch arrival-time monitors (BAM) with optical synchronization demonstrated resolution in the range of 10 – 40 fs for bunch charges above 50 pC. For even lower bunch charges and, thus for only few-fs long accelerator pulses, the sensitivity of BAMs need to be further improved. One of the key components of any optically-synchronized BAM is a high-speed electro-optical modulator (EOM) that imprints the electrical pulse from a pick-up structure onto the optical synchronization signal. Here we present the status of the development of a wideband photonic-integrated EOM with low drive voltages which could potentially enable BAMs with sub-10 fs timing accuracy for bunch charges down to 1 pC.
