The Jaynes-Cummings Hamiltonian is at the core of cavity quantum electrodynamics; however, it relies on bound-electron emitters fundamentally limited by the binding Coulomb potential. In this work, we propose theoretically a new approach to realizing the Jaynes-Cummings model using low-energy free electrons coupled to dielectric microcavities and exemplify several quantum technologies made possible by this approach. Using quantum recoil, a large detuning inhibits the emission of multiple consecutive photons, effectively transforming the free electron into a few-level system coupled to the cavity mode. We show that this approach can be used for generation of single photons, photon pairs, and even a quantum SWAP gate between a photon and a free electron, with unity efficiency and high fidelity. Tunable by their kinetic energy, quantum free electrons are inherently versatile emitters with an engineerable emission wavelength. Hence, they pave the way toward new possibilities for quantum interconnects between photonic platforms at disparate spectral regimes.

中文翻译：

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低能自由电子与腔光子之间的杰恩斯-卡明斯相互作用

Jaynes-Cummings 哈密顿量是腔量子电动力学的核心；然而，它依赖于束缚电子发射器，从根本上受到束缚库仑势的限制。在这项工作中，我们从理论上提出了一种使用低能自由电子耦合到介电微腔来实现 Jaynes-Cummings 模型的新方法，并举例说明了通过这种方法实现的几种量子技术。利用量子反冲，大的失谐抑制了多个连续光子的发射，有效地将自由电子转变为与腔模式耦合的少能级系统。我们证明，这种方法可用于生成单光子、光子对，甚至光子和自由电子之间的量子交换门，具有统一效率和高保真度。量子自由电子可通过其动能进行调节，本质上是具有可设计发射波长的多功能发射器。因此，它们为不同光谱范围的光子平台之间的量子互连的新可能性铺平了道路。