Single-Shot Spectral-Temporal Ultrafast Photography: Fundamentals, Methods, and Applications

Recent progress in fundamental science and technology requires observing ultrafast dynamics that are extremely difficult to repeat and with increasing spatial-temporal complexity. Correspondingly, ultrafast imaging methods must realize continuous recording with ultrahigh frame rates and numerous frames in a single shot. To overcome this challenge, spectral-temporal ultrafast photography, which uses spectral dimensions of an observing pulse to detect the temporal dimensions of an ultrafast process, has earned excellent performance. This rapid-developing field holds advantages over other single-shot ultrafast imaging methods with nonreciprocal detecting dimensions using unique spectral-temporal reciprocities. Until now, spectral-temporal ultrafast photography has been capable of hundreds of frames in single-shot detection, a detecting window from femtoseconds to nanoseconds, and tens of femtoseconds in temporal resolution. Here, we comprehensively survey the state-of-the-art spectral-temporal ultrafast imaging methods. Two main steps, the generation of the spectral-temporal observing pulse and the restoration of the spectral image sequence, are discussed. Finally, we summarized current methods and envisioned prospects for advancement.