Comment on “Synthesis and Direct Sampling of Single-Cycle Light Transients by Electron Tunneling in a Nanodevice”

Abstract

A recent article by Luo et al., “Synthesis and Direct Sampling of Single-Cycle Light Transients by Electron Tunneling in a Nanodevice.” ACS Photonics 2023, 10, 2866–2873, describes the use of photoassisted tunneling from nanostructures to sample synthesized optical field transients in the time domain. The authors claim that with their measurement approach the single-photon absorption process they used for detection is sufficient for the complete characterization of the measured optical field transients in the time domain, thus providing complete amplitude and phase information in the frequency domain. However, our own analysis shows that if the experiments described in the manuscript behave in the way the authors describe, it would in fact not be possible to retrieve complete optical field information. Our analysis finds that measurements described by the authors should only provide spectral amplitude information no different from the information provided by a spectrometer. As a result of our findings, we have significant concerns regarding the validity of the key claims of the paper.