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arXiv · 2405.06560

Quantum computing and quantum optics with recoiled free electrons

Maxim Sirotin·Andrei Rasputnyi·Tomáš Chlouba·Roy Shiloh·Peter Hommelhoff
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Abstract

Free electrons interacting coherently with optical fields provide a powerful platform for quantum simulation and quantum control. For kiloelectron-volt electron energies, even optical photon emission and absorption produce appreciable quantum recoils, endowing the electron with a discrete and controllable energy ladder. Starting from relativistic quantum electrodynamics, we derive an exact recoil-resolved interaction Hamiltonian in a traveling wave picture. The resulting recoil ladder forms a high-dimensional qudit with programmable couplings and sufficient controllability for universal quantum computation. We demonstrate applications to quantum simulation, including one-dimensional analogue black-hole models including Hawking radiation physics, and to quantum information processing, where multiple logical qubits and high-fidelity gates can be realized with a single electron. In parallel, the same recoil-enabled dynamics enable the controlled creation of complex hybrid electron--photon states, in which engineered ladder transitions imprint nonclassical correlations and structure onto the emitted light. Together, these results establish recoiled free electrons as a versatile platform bridging quantum optics, Hamiltonian engineering, and quantum simulation.

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Maxim Sirotin, Andrei Rasputnyi, Tomáš Chlouba, Roy Shiloh, Peter Hommelhoff. 2026-05-19. Quantum computing and quantum optics with recoiled free electrons. https://arxiv.org/abs/2405.06560

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