Extreme waveform compression with a nonlinear temporal focusing mirror

Dealing with the increase in digital optical data transmission rates requires innovative approaches for stretching or compressing optical waveforms beyond the bandwidth limitations inherent in conventional electro‐optical systems. To this aim, photonic platforms exploiting ultrafast nonlinear phenomena have been successfully applied to the temporal stretching of optical waveforms. However, the inverse process, that is, the temporal compression of arbitrary lightwaves, has remained largely unexploited so far. Here we present an experimental demonstration of the extreme temporal compression of optical waveforms, including non‐trivial on‐demand time reversal. The method is based on counterpropagating degenerate four‐photon interaction in birefringent optical fibres. We demonstrate the performance of this system by generating the ultrafast replica of data packets with record temporal compression factors ranging from 4,350 to 13,000. This approach is scalable and offers great promise for ultrafast arbitrary optical waveform generation and related applications. Temporal compression of optical waveforms with compression factors up to 13,000 is demonstrated by exploiting four-wave mixing in a birefringent fibre.