Passive Photonic CZ Gate with Two-Level Emitters in Chiral Multimode Waveguide QED

PRX Quantum, Journal Year: 2025, Volume and Issue: 6(1)

Published: March 5, 2025

Engineering deterministic photonic gates with simple resources is one of the long-standing challenges in quantum computing. Here, we design a passive conditional gate between copropagating photons using an array only two-level emitters. The key resource to harness effective photon-photon interaction induced by chiral coupling emitter two waveguide modes different resonant momenta at emitter’s transition frequency. By studying system’s multiphoton scattering response, demonstrate that, certain limits, this configuration induces nonlinear π-phase shift polariton eigenstates system without distorting spectrally wave packets. Then, show how phase engineer conditional, qubit encodings, fidelity arbitrarily close 1 limit large number emitters and efficiency. Our can be implemented topological setups multiple chiral-edge modes, opening their use for information processing, or other where such light-matter couplings effectively obtained, as optical fibers photonic-crystal microwave waveguides. Published American Physical Society 2025

Language: Английский

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Controlling Markovianity with Chiral Giant Atoms

Physical Review Letters, Journal Year: 2024, Volume and Issue: 133(6)

Published: Aug. 9, 2024

Giant artificial atoms are promising and flexible building blocks for the implementation of analog quantum simulators. They realized via a multilocal pattern couplings two-level systems to waveguide, or two-dimensional photonic bath. A hallmark giant-atom physics is their non-Markovian character in form self-coherent feedback, leading, e.g., nonexponential atomic decay. The timescale non-Markovianity essentially given by time delay proportional distance between various coupling points. In parallel, with state-of-the-art experimental setups, it possible engineer complex phases atom-light couplings. Such simulate an magnetic field, yielding chiral behavior system. Here, we report surprising connection these two seemingly unrelated features giant atoms, showing that chirality atom controls its Markovianity. particular, adjusting couplings' phases, can, counterintuitively, enter exact Markovian regime, irrespectively any inherent delay. We illustrate this mechanism as interference process collision model picture. Our findings significantly advance understanding physics, open new avenues control nanophotonic networks.

Language: Английский

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Single-photon scattering in giant-atom waveguide systems with chiral coupling

Physical review. A/Physical review, A, Journal Year: 2024, Volume and Issue: 109(6)

Published: June 5, 2024

We study single-photon scattering spectra of a giant atom chirally coupled to one-dimensional waveguide at multiple connection points, and examine chirality-induced effects in the spectra. show that transmission typically possess an anti-Lorentzian lineshape with nonzero minimum, but by engineering chirality multipoint coupling, spectrum incident photon can undergo transition from complete total reflection frequency ``windows,'' where width for each window be flexibly tuned fixed detuning. Moreover, we perfect nonreciprocal achieved due interplay between internal atomic spontaneous emission external decay waveguide, contrast induced non-Markovian retardation effect. also consider effect on spectra, which allows photonic band gap even only two chiral coupling points. The giant-atom-waveguide system is promising candidate realizing routers channels.

Language: Английский

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Quantum theory of non-Hermitian optical binding between nanoparticles

Physical review. A/Physical review, A, Journal Year: 2024, Volume and Issue: 110(6)

Published: Dec. 3, 2024

Recent experiments demonstrate highly tunable nonreciprocal coupling between levitated nanoparticles due to optical binding [J. Rieser et al., Science 377, 987 (2022)]. In view of recent cooling the quantum regime, we here develop theory small dielectric objects interacting via forces and torques induced by scattered tweezer photons. The interaction is fundamentally non-Hermitian accompanied correlated noise. We present corresponding Markovian master equation show how reach unidirectional coupling. Our work provides theoretical tools for exploring exploiting rich physics nonreciprocally coupled nanoparticle arrays.

Language: Английский

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Circuit QED with giant atoms coupling to left-handed superlattice metamaterials

Physical review. A/Physical review, A, Journal Year: 2024, Volume and Issue: 109(1)

Published: Jan. 18, 2024

Giant atoms, where the dipole approximation ceases to be valid, allow us observe unconventional quantum optical phenomena arising from interference and time-delay effects. Most previous studies consider giant atoms coupling conventional materials with right-handed dispersion. In this study, we first investigate dynamics of a atom interacting left-handed superlattice metamaterials. Different those counterparts, superlattices exhibit an asymmetric band gap generated by anomalous dispersive bands Bragg scattering bands. With assumption that is in resonance continuous energy band, spontaneous emission will undergo periodic enhancement or suppression due effect. At resonant position, there significant discrepancy decay rates between upper lower which arises differences group velocity. Second, explore non-Markovian considering emitter's frequency outside bound states induced two points. By employing both analytical numerical methods, demonstrate steady atomic population periodically modulated, driven variations size atom. The presence edges leads diverse dynamics. Finally, case identical emitters coupled waveguide find within undergoes exchange through mechanism Rabi oscillations.

Language: Английский

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Predicting correlations in superradiant emission from a cascaded quantum system

Physical review. A/Physical review, A, Journal Year: 2024, Volume and Issue: 110(4)

Published: Oct. 17, 2024

Language: Английский

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Nonreciprocal single-photon scattering in giant-spin-ensemble–waveguide magnonics

Physical review. A/Physical review, A, Journal Year: 2023, Volume and Issue: 108(6)

Published: Dec. 26, 2023

We study nonreciprocal single-photon scattering in a giant-spin-ensemble (GSE)--waveguide magnonics system where the GSE constructed by yttrium iron garnet sphere interacts twice with waveguide via two separated coupling points. It is shown that generation of nonreciprocity arises from synergy breaking time-reversal symmetry induced chiral and intrinsic dissipation magnon mode case single waveguide. The accumulated phase caused photon propagating between points can be powerful tool to control due quantum interference effects. Compared Markovian regime, transmission exhibits peculiarly properties non-Markovian regime. Multiple narrow windows are observed. Non-Markovianity break decoupling phenomenon regime non-Markovianity-induced demonstrated. extend coupled double-waveguide structure explore design devices. A high-efficiency tunable multifrequency targeted router circulator operational bandwidth achieved. Our results provide an effective avenue for manipulation have potential applications designing magnon-based devices constructing integrated network.

Language: Английский

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Catch and release of propagating bosonic field with non-Markovian giant atom

New Journal of Physics, Journal Year: 2023, Volume and Issue: 26(1), P. 013025 - 013025

Published: Dec. 27, 2023

Abstract The non-Markovianity of physical systems is considered to be a valuable resource that has potential applications quantum information processing. control traveling fields encoded with (flying qubit) crucial for networks. In this work, we propose catch and release the propagating photon/phonon non-Markovian giant atom, which coupled environment via multiple coupling points. Based on Heisenberg equation motion atom field operators, calculate time-dependent scattering coefficients from linear response theory define criteria atom. We analyze numerically verify bound states due can harnessed bosonic demand by tuning parameters

Language: Английский

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Nonreciprocal Synchronization of Active Quantum Spins

Physical Review X, Journal Year: 2025, Volume and Issue: 15(1)

Published: Jan. 21, 2025

Active agents are capable of exerting nonreciprocal forces upon one another. For instance, agent, say A, may attract another agent B while B repels A. These antagonistic interactions have been extensively studied in classical systems, revealing a wealth exciting phenomena such as novel phase transitions and traveling-wave states. Whether these can originate quantum many-body systems is an open issue, proposals for their realization lacking. In this work, we present model two species spins that interact way the attraction-repulsion type. We propose implementation based on atomic ensembles coupled via chiral waveguides featuring both braided nonbraided geometries. The active due to presence local gain, which allows them synchronize. thermodynamic limit, show result transition time-crystalline states, associated with spontaneous breaking parity-time symmetry. establish how symmetry emerges from microscopic model. finite number spins, signatures time-crystal still be identified by inspecting equal-time or two-time correlation functions. Remarkably, continuous monitoring output field induces state: state finite-size system, spontaneously broken. Our work lays foundation explore matter. Published American Physical Society 2025

Language: Английский

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Directional emission of a broadband squeezed microwave field

Physical review. A/Physical review, A, Journal Year: 2025, Volume and Issue: 111(2)

Published: Feb. 4, 2025

Language: Английский

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