Frequency-Domain Streak Camera for Ultrafast Imaging of Evolving Light-Velocity Objects

We demonstrate a frequency-domain streak camera (FDSC) that captures the picosecond evolution of luminal velocity refractive index structures in a single shot. In FDSC, a probe-reference pulse pair propagates obliquely to an evolving index structure generated by a pump pulse in glass, supplementing a conventional frequency-domain holographic (FDH) probe-reference pair that co-propagates with the pump. A single spectrometer acquires data from both probes via spatial or temporal multiplexing, demonstrating the possibility of frequency-domain tomography (FDT) in which a single spectrometer processes data from over a dozen of probing angles.