Chip-based attosecond time-domain spectroscopy

Time-domain sampling of arbitrary electric fields with sub-cycle resolution enables complementary time-frequency analyses of a system's electromagnetic response. Time-domain spectroscopy has many applications from tracking physical phenomena to biology and medicine. Commercial optical-field-resolved time-domain spectroscopy systems operating in the THz regime, capable of sub-cycle field sampling, are now readily available and often used for industrial and scientific application with favorable outcome. Despite these compelling methodologies, scaling such techniques to the visible and near-IR spectral regimes has remained challenging, and seemingly demands high-energy optical sources and complicated optical apparatuses. We have explored chip-based strong-field tunneling emission from nanostructures as a new route for optical-field driven electronic systems. Our approach has developed and demonstrated an all-on-chip, optoelectronic device capable of sampling arbitrary, low-energy, waveforms under ambient conditions with attosecond time-resolution. This detector uses strong field driven photoemission from plasmonic nanoantennas to generate attosecond electron bursts to probe the electric field of weak optical waveforms, enabling a bandwidth greater than 1 PHz. Additionally, our measurements can directly reveal the localized plasmonic dynamics of the emitting nanoantennas in situ. Our work demonstrates a compact and integratable sampling technology with the requisite bandwidth and field sensitivity for real-world applications, enabling time-domain, optical-field-resolved spectroscopy of low-energy optical waveforms spanning visible to mid-infrared and even THz wavelengths.