Low-Energy Free-Electron Nonclassical Lasing

TL;DR

This paper presents a theoretical framework for nonclassical lasing using slow free electrons in photonic structures, enabling tunable, high-fidelity quantum light emission at room temperature with potential for scalable quantum technologies.

Contribution

It introduces a novel theory of nonclassical lasing driven by incoherent free electrons in photonic cavities, including quantum state trapping and tunable photon emission.

Findings

Nonclassical lasing with sub-Poissonian photon statistics demonstrated.

High-fidelity Fock states achieved at room temperature.

Photon frequency tunable via electron velocity.

Abstract

Harnessing a beam of slow free electrons in artificial photonic structures offers a powerful, tunable platform for generating nonclassical light without the need for heavy physical equipment. Here we present a theory of nonclassical lasing, demonstrating how incoherent electrons in photonic crystal cavities can coherently emit photons through collective dynamics. When photon emission rate exceeds cavity losses, nonclassical lasing with sub-Poissonian photon statistics emerges, driven by multi-photon Rabi oscillations. At specific coupling strengths, quantum state trapping effect emerges, producing high-fidelity Fock states at room temperature (e.g. nearly 90%-fidelity of four photon Fock state). Notably, the frequency of the emitted photons can be readily tuned via the velocity of the injected electrons to match cavity modes. This approach supports photonic integration and offers a scalable, energy-efficient platform for room-temperature quantum light sources and advanced studies in quantum electrodynamics.