Simple and monolithic picosecond pulse shaper based on fiber Bragg gratings

In this contribution we present a simple and robust pulse shaping device based on coherent pulse stacking. The device is based on fiber Bragg gratings written in a polarisation maintaining step index fiber and a fiber optical circulator. Up to four pulse replicas are reflected by fiber Bragg gratings and interfere at the output of the device. Temperature control allows tuning of the relative pulse amplitudes and phases of the pulse replicas. We experimentally demonstrated 235 ps and 416 ps long flattop pulses with rising and falling edges shorter than 100 ps. In contrast to other pulse shaping techniques the presented setup is robust, alignment free, provides excellent beam quality and is also suitable for pulse durations up to several nanoseconds.