Engineering & Technologyarticle2026-08-22

Phase-matching-free sensing with undetected light using a nonlinear thin-film metasurface

Open access0 citations

Abstract

Abstract In this article, we report classical sensing with undetected light at a wavelength of 1500 nm, detected on a silicon camera at 580 nm, using four-wave mixing from a plasmonic metasurface. The bidirectional nonlinear scattering due to inherent reflections from such thin nonlinear materials modifies their operation within a nonlinear interferometer. The theoretical model for visibility accounting for bidirectionality as well as pulsed illumination accurately predicts visibility in the system as a function of transmission in the near-infrared seed (idler) arm. Spectrally resolving the visible signal emission evaluates the total dispersion within the interferometer, highlighting the prospect of ultrafast sensing with undetected photons.

// Source

View paper (DOI)Open access versionOpenAlexNature CommunicationsPublished 2026-08-22

Authors: Toby Severs Millard, Nathan R. Gemmell, Ross C. Schofield, Mohsen Rahmani, Alex S. Clark, Chris C. Phillips, Rupert F. Oulton

Institutions: Imperial College London, University of Bristol, Nottingham Trent University, National Physical Laboratory, Bristol Robotics Laboratory