Universal and Ultrafast Quantum Computation Based on Free-Electron-Polariton Blockade

PRX Quantum, Год журнала: 2024, Номер 5(1)

Опубликована: Март 6, 2024

Cavity QED, wherein a quantum emitter is coupled to electromagnetic cavity modes, powerful platform for implementing sensors, memories, and networks. However, due the fundamental trade-off between gate fidelity execution time, as well limited scalability, use of QED computation was overtaken by other architectures. Here, we introduce new element into QED—a free charged particle, acting flying qubit. Using electrons specific example, demonstrate that our approach enables ultrafast, deterministic, universal discrete-variable in cavity-QED-based architecture, with potentially improved scalability. Our proposal hinges on novel excitation blockade mechanism resonant interaction free-electron polariton. This nonlinear faster several orders magnitude respect current photon-based cavity-QED gates, enjoys wide tunability can fidelities close unity. Furthermore, scheme ubiquitous any nonlinearity, either light-matter coupling Jaynes-Cummings model or photon-photon interactions Kerr-type many-body system. In addition promising advancements computation, paves way towards ultrafast deterministic generation highly entangled photonic graph states applicable technologies involving QED. Published American Physical Society 2024

Язык: Английский

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Probing electron-photon entanglement using a quantum eraser

Physical review. A/Physical review, A, Год журнала: 2025, Номер 111(1)

Опубликована: Янв. 9, 2025

We propose a tangible experimental scheme for demonstrating quantum entanglement between swift electrons and light, relying on coherent cathodoluminescence photon generation in transmission electron microscope, eraser setup formation verification of entanglement. The free with light is key to developing free-electron optics its potential applications such as sensing, novel photonic state generation, electrons. Published by the American Physical Society 2025

Язык: Английский

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Maximal Quantum Interaction between Free Electrons and Photons

Physical Review Letters, Год журнала: 2025, Номер 134(4)

Опубликована: Янв. 31, 2025

The emerging field of free-electron quantum optics enables electron-photon entanglement and holds the potential for generating nontrivial photon states information processing. Although recent experimental studies have entered regime, rapid theoretical developments predict that qualitatively unique phenomena only emerge beyond a certain interaction strength. It is thus pertinent to identify maximal strength materials, geometries, particle energies enable one approach it. We derive an upper limit vacuum between free electrons single-mode photons, which illuminates conditions strongest interaction. Crucially, we obtain explicit energy selection recipe photons achieve at arbitrary separations two optimal regimes favoring either fast or slow over those with intermediate velocities. validate by analytical numerical calculations on canonical geometries provide near-optimal designs indicating feasibility strong interactions. Our findings offer fundamental intuition maximizing practical design rules future experiments electron-mediated photon-photon entanglement. They should also evaluation key metrics applications such as maximum power radiation sources acceleration gradient dielectric laser accelerators.

Язык: Английский

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Upper Bound for the Quantum Coupling between Free Electrons and Photons

Physical Review Letters, Год журнала: 2025, Номер 134(4)

Опубликована: Янв. 31, 2025

The quantum interaction between free electrons and photons is fundamental to free-electron-based light sources free-electron optics applications. A large coupling generally desired. In this Letter, I obtain the upper bound for photons. has a straightforward expression can be applied broad range of optical materials, especially widely used low-loss photonic materials. depends on medium, velocity, separation electron medium. With simple structures, numerically calculated coefficient reach ∼99% bound. This study provides practical guidance strong

Язык: Английский

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Unveiling the nature of cathodoluminescence from photon statistics

Communications Physics, Год журнала: 2025, Номер 8(1)

Опубликована: Фев. 5, 2025

Язык: Английский

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Free-Space Optical Modulation of Free Electrons in the Continuous-Wave Regime

Physical Review Letters, Год журнала: 2025, Номер 134(12)

Опубликована: Март 26, 2025

The coherent interaction between free electrons and optical fields can produce free-electron compression push the temporal resolution of ultrafast electron microscopy to attosecond regime. However, a large electron-light is required attain strong compression, generally necessitating short light pulses combined with scattering at nanostructures. Here, we theoretically investigate an alternative configuration based on stimulated Compton scattering, whereby two counterpropagating Gaussian beams induce energy jumps in collinear beam by multiples their photon-energy difference. Strong recoil effects are produced extending over millimetric distances, enabling dramatic increase substantially reshaping spectra for affordable laser powers. Beyond its fundamental interest, our Letter introduces practical scheme achieve continuous without involving material structures.

Язык: Английский

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Tunable quantum light by modulated free electrons

Nanophotonics, Год журнала: 2025, Номер unknown

Опубликована: Май 21, 2025

Abstract Nonclassical states of light are fundamental in various applications, spanning quantum computation to enhanced sensing. Fast free electrons, which emit into photonic structures through the mechanism spontaneous emission, represent a promising platform for generating diverse types states. Indeed, intrinsic connection between input electron wave function and output field suggests that electron-shaping schemes, based on light-induced scattering, facilitate their synthesis. In this article, we present theoretical framework capable predicting final optical density matrix emitted by generic N -electron state can also account post-sample energy filtering. By using such framework, study modulation-dependent fluctuations emission identify regions superradiant scaling characterized Poissonian super-Poissonian statistics. context, predict high- modulated pulses yield tenfold shot-noise suppression estimation electron-light coupling when radiation intensity is analyzed. single-electron case, show how coherent with nearly 90 % purity be formed pre-filtering portion spectrum after modulation, non-Gaussian generated precise measurement. Furthermore, strategy combining single-stage modulation post-filtering harness tailored states, as squeezed vacuum, cat, triangular cat fidelities close 100 %.

Язык: Английский

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Phase-locked photon–electron interaction without a laser

Nature Physics, Год журнала: 2023, Номер 19(6), С. 869 - 876

Опубликована: Фев. 23, 2023

Abstract Ultrafast photon–electron spectroscopy in electron microscopes commonly requires ultrafast laser setups. Photoemission from an engineered source is used to generate pulsed electrons, interacting with a sample excited by the pulse at known time delay. Thus, developing microscope demands exploitation of extrinsic excitations and complex synchronization schemes. Here we present inverse approach introduce internal radiation sources based on cathodoluminescence spectroscopy. Our compact method sequential interaction beam electron-driven photon investigated sample. Such generates phase-locked photons that are mutually coherent near-field distribution swift electron. We confirm mutual frequency momentum-dependent correlation determine degree coherence up 27%. With this level coherence, were able perform spectral interferometry microscope. has advantage being simple, operating continuous beams. It will open door local quantum materials, single-photon systems exciton–polaritonic samples nanometre resolution.

Язык: Английский

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Electron-Photon Quantum State Heralding Using Photonic Integrated Circuits

PRX Quantum, Год журнала: 2023, Номер 4(2)

Опубликована: Июнь 26, 2023

Recently, integrated photonic circuits have brought new capabilities to electron microscopy and been used demonstrate efficient phase modulation electron-photon correlations. Here, we quantitatively analyze the feasibility of high-fidelity high-purity quantum state heralding using a free circuit with parametric coupling, propose schemes shape useful states in different application scenarios. Adopting dissipative electrodynamics treatment, formulate framework for coupling electrons waveguide spatial-temporal modes. To avoid multimode-coupling-induced decoherence, show that proper design, interaction can be reduced single-mode quasi-TM00 mode. In limit, go beyond conventional ladder energy correlations within subspace still lead fundamental purity fidelity limit on complex optical preparations through schemes. We applications use this underlying correlation their advantage, but also imposed limitations general overcome by an experimentally feasible length, showing its promise as platform free-electron optics.5 MoreReceived 20 June 2022Revised 24 February 2023Accepted 1 2023DOI:https://doi.org/10.1103/PRXQuantum.4.020351Published American Physical Society under terms Creative Commons Attribution 4.0 International license. Further distribution work must maintain attribution author(s) published article's title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasIntegrated opticsSpontaneous emissionTechniquesElectron microscopyAtomic, Molecular & OpticalCondensed Matter, Materials Applied PhysicsQuantum Information

Язык: Английский

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Jaynes-Cummings interaction between low-energy free electrons and cavity photons

Science Advances, Год журнала: 2023, Номер 9(22)

Опубликована: Май 31, 2023

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

Язык: Английский

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