Mina R. Bionta, Felix Ritzkowsky, Marco Turchetti, Yujia Yang, Dario Cattozzo Mor, William P. Putnam, Franz X. Kärtner, Karl K. Berggren & Phillip D. Keathley

DOI: 10.1038/s41566-021–00792‑0 


We demonstrate an on-chip, optoelectronic device capable of sampling arbitrary, low-energy, near-infrared waveforms under ambient conditions with sub-optical-cycle resolution. Our detector uses field-driven photoemission from resonant nanoantennas to create attosecond electron bursts that probe the electric field of weak optical waveforms. Using these devices, we sampled the electric fields of ~5 fJ (6.4 MV m−1), few-cycle, near-infrared waveforms using ~50 pJ (0.64 GV m−1) near-infrared driving pulses. Beyond sampling these weak optical waveforms, our measurements directly reveal the localized plasmonic dynamics of the emitting nanoantennas in situ. Applications include broadband time-domain spectroscopy of molecular fingerprints from the visible region through the infrared, time-domain analysis of nonlinear phenomena and detailed investigations of strong-field light–matter interactions.