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arXiv · 2208.02103

Electro-Optical Sampling of Single-Cycle THz Fields with Single-Photon Detectors

Taylor Shields·Adetunmise C. Dada·Lennart Hirsch·Seungjin Yoon·Jonathan M. R. Weaver·Daniele Faccio·Lucia Caspani·Marco Peccianti·Matteo Clerici
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Abstract

Electro-optical sampling of Terahertz fields with ultrashort pulsed probes is a well-established approach for directly measuring the electric field of THz radiation. This technique usually relies on balanced detection to record the optical phase shift brought by THz-induced birefringence. The sensitivity of electro-optical sampling is, therefore, limited by the shot noise of the probe pulse, and improvements could be achieved using quantum metrology approaches using, e.g., NOON states for Heisenberg-limited phase estimation. We report on our experiments on THz electro-optical sampling using single-photon detectors and a weak squeezed vacuum field as the optical probe. Our approach achieves field sensitivity limited by the probe state statistical properties using phase-locked single-photon detectors and paves the way for further studies targeting quantum-enhanced THz sensing.

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Taylor Shields, Adetunmise C. Dada, Lennart Hirsch, Seungjin Yoon, Jonathan M. R. Weaver, Daniele Faccio, Lucia Caspani, Marco Peccianti, Matteo Clerici. 2022-08-03. Electro-Optical Sampling of Single-Cycle THz Fields with Single-Photon Detectors. https://doi.org/10.3390/s22239432

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