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Physical Review Letters

Photonic Quantum State Tomography Using Free Electrons

Alexey A. Gorlach, Salomon Malka, Aviv Karnieli, Raphael Dahan, Eliahu Cohen, Avi Pe’er, Ido E. Kaminer

Published Dec 20, 2024• 10 citations
Publisher

Abstract

The tomography of photonic quantum states is key in quantum optics, impacting quantum sensing, computing, and communication. Conventional detectors are limited in their temporal and spatial resolution, hampering high-rate quantum communication and local addressing of photonic circuits. Here, we propose to utilize free electron-photon interactions for quantum state tomography, introducing electron homodyne detection with potential for femtosecond-temporal and nanometer-spatial resolutions. The detectable quantum information level depends on the electron-photon interaction strength. Our Letter opens avenues for free-electron-based photodetection utilizing the ultrafast, subwavelength, nondestructive nature of free electrons.

DOI
10.1103/physrevlett.133.250801

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