- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Complete and Nondestructive Atomic Greenberger-Horne-Zeilinger-State Analysis Assisted by Invariant-Based Inverse Engineering
摘要： A protocol to realize complete and nondestructive atomic Greenberger–Horne–Zeilinger (GHZ)-state analysis in cavity quantum electrodynamics (QED) systems is presented. In this protocol, the three information-carrier atoms and the three auxiliary atoms are trapped in six separated cavities, respectively. After ten-step operations, the information for distinguishing the eight different GHZ states of the three information-carrier atoms is encoded on the auxiliary atoms. Thus, by means of detecting the auxiliary atoms, complete and nondestructive GHZ-state analysis with high success probability is realized. Moreover, the driving pulses of operations are designed as a simple superposition of Gaussian or trigonometric functions by using the invariant-based inverse engineering. Therefore, the protocol can be realized experimentally and applied in some quantum information tasks based on complete GHZ-state analysis with less physical entanglement resource.
关键词： GHZ-state analysis,cavity quantum electrodynamics system,invariant-based inverse engineering
更新于2025-09-23 15:23:52
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Jarzynski equality for superconducting optical cavities: An alternative path to determine Helmholtz free energy
摘要： A superconducting cavity model was proposed as a way to experimentally investigate the work performed in a quantum system. We found a simple mathematical relation between the free energy variation and visibility measurement in quantum cavity context. If we consider the difference of Hamiltonian at time t0 and tλ (protocol time) as a quantum work, then the Jarzynski equality is valid and the visibility can be used to determine the work done on the cavity.
关键词： quantum Jarzynski equality,quantum heat,quantum work,cavity quantum electrodynamics
更新于2025-09-23 15:22:29
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Three-player polaritons: nonadiabatic fingerprints in an entangled atom-molecule-photon system
摘要： A quantum system composed of a molecule and an atomic ensemble, con?ned in a microscopic cavity, is investigated theoretically. The indirect coupling between atoms and the molecule, realized by their interaction with the cavity radiation mode, leads to a coherent mixing of atomic and molecular states. It is shown for the Na2 molecule that by changing the cavity wavelength and the molecular states, and at strong enough cavity ?eld strengths hybrid atom-molecule-photon polaritons are formed. Moreover, an unforeseen intensity borrowing e?ect, which can be seen as a strong nonadiabatic ?ngerprint, is identi?ed in the atomic transition peak, originating from the contamination of the atomic excited state with excited molecular rovibronic states.
关键词： nonadiabatic,entangled atom-molecule-photon system,intensity borrowing effect,polaritons,cavity quantum electrodynamics
更新于2025-09-23 15:19:57
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Strong Coupling of a Single Photon to a Magnetic Vortex
摘要： Strong light-matter coupling means that cavity photons and other type of matter excitations are coherently exchanged. It is used to couple different qubits (matter) via a quantum bus (photons) or to communicate different type of excitations, e.g., transducing light into phonons or magnons. An unexplored, so far, interface is the coupling between light and topologically protected particle-like excitations as magnetic domain walls, skyrmions or vortices. Here, we show theoretically that a single photon living in a superconducting cavity can be strongly coupled to the gyrotropic mode of a magnetic vortex in a nanodisc. We combine numerical and analytical calculations for a superconducting coplanar waveguide resonator and different realizations of the nanodisc (materials and sizes). We show that, for enhancing the coupling, constrictions fabricated in the resonator are crucial, allowing to reach the strong coupling in CoFe discs of radius 200 ? 400 nm having resonance frequencies of few GHz. The strong coupling regime permits to coherently exchange a single photon and quanta of vortex gyration. Thus, our calculations show that the device proposed here serves as a transducer between photons and gyrating vortices, opening the way to complement superconducting qubits with topologically protected spin-excitations like vortices or skyrmions. We finish by discussing potential applications in quantum data processing based on the exploitation of the vortex as a short-wavelength magnon emitter.
关键词： cavity quantum electrodynamics,topological magnetism,coplanar waveguide resonators,nanoresonator,Magnetic vortex,light-matter interaction
更新于2025-09-23 15:19:57
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Quantum stabilization of microcavity excitation in a coupled microcavitya??half-cavity system
摘要： We analyze the quantum dynamics of a two-level emitter in a resonant microcavity with optical feedback provided by a distant mirror (i.e., a half cavity) with a focus on stabilizing the emitter-microcavity subsystem. Our treatment is fully carried out in the framework of cavity quantum electrodynamics. Specifically, we focus on the dynamics of a perturbed subradiant state of the emitter-microcavity subsystem to ascertain its stability (existence of time oscillatory solutions around the candidate state) or lack thereof. In particular, we find conditions under which multiple feedback modes of the half cavity contribute to the stability, showing certain analogies with the Lang-Kobayashi equations, which describe a laser diode subject to classical optical feedback.
关键词： optical feedback,microcavity,Lang-Kobayashi equations,quantum dynamics,two-level emitter,cavity quantum electrodynamics,stability,subradiant state
更新于2025-09-19 17:13:59
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Improving photon antibunching with two dipole-coupled atoms in whispering-gallery-mode microresonators
摘要： In the two-atom or multiatom system, the atoms can interact with each other through exchange of virtual photon. This kind of energy exchange is often referred as the dipole-dipole interaction (DDI). Here we consider this DDI system consisting of a pair of two-level atoms strongly coupled with a bimodal whispering-gallery-mode (WGM) microresonator which is driven by an external laser field. Our aim is to explore the photon correlation characteristics of the proposed architecture using realistic experimental parameter values. We compare in detail the quality of photon antibunching (i.e., the smallness of the second-order correlation function) from three involved configurations in cavity quantum electrodynamics (QED): (i) only one two-level atom, (ii) two far apart two-level atoms without DDI, and (iii) two DDI (dipole-coupled) two-level atoms are respectively coupled to the driven WGM microresonator through the evanescent field. We clearly show that the DDI between both atoms can distinctly enhance the photon antibunching even in the weak-coupling regime in configuration (iii) with feature-rich line shapes. We also find that the photon antibunching can be modulated by properly adjusting the atom-cavity coupling strength. In addition, we display that this strong photon antibunching is robust against the cooperative atomic decay. Our DDI-based cavity QED scheme may provide an alternative way to the construction of integrated on-chip single-photon sources.
关键词： photon antibunching,whispering-gallery-mode microresonators,single-photon sources,dipole-dipole interaction,cavity quantum electrodynamics
更新于2025-09-19 17:13:59
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The interplay of electron-photon and cavity-environment coupling on the electron transport through a quantum dot system
摘要： We theoretically investigate the characteristics of the electron transport through a two-dimensional a quantum dot system in the xy-plane coupled to a photon cavity and a photon reservoir, the environment. The electron-photon coupling, gγ, and the cavity-reservoir coupling, κ, are tuned to study the system in the weak, gγ ≤ κ, and the strong coupling regime, gγ > κ. An enhancement of current is both seen with increasing gγ and κ in the weak coupling regime for both x- and y-polarization of the photon field. This is a direct consequence of the Purcell effect. The current enhancement is due to the contribution of the photon replica states to the electron transport in which intraband transitions play an important role. The properties of the electron transport are drastically changed in the strong coupling regime with an x-polarized photon field in which the current is suppressed with increasing gγ, but it is still increasing with κ. This behavior of the current is related to the population of purely electronic states and depopulation of photon replica states.
关键词： Quantum master equation,Quantum Dot,Cavity-Quantum electrodynamics,Quantum transport,Purcell effect
更新于2025-09-16 10:30:52
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Fano resonance induced fast to slow light in a hybrid semiconductor quantum dot and metal nanoparticle system
摘要： We theoretically demonstrate the Fano resonance and the conversion from fast to slow light in a hybrid semiconductor quantum dot (SQDs)-metal nanoparticle (MNPs) with cavity quantum electrodynamics treatment. The absorption spectra of the weak probe field exhibit a series of asymmetric Fano line shapes and their related optical propagation properties, such as fast and slow light effects, are investigated based on the hybrid system for suitable parametric regimes. Further, the transparency windows (i.e. the absorption dip approaches zero) in the probe absorption spectra are accompanied by the rapid steep dispersion of the Fano resonance profile, which promises the slow or fast light effect, and even tunable fast-to-slow light propagation (or vice versa) can be achieved by controlling different parameter regimes. Therefore the investigation may indicate promising applications in quantum information processing based on the hybrid SQD-MNP system.
关键词： semiconductor quantum dots,cavity quantum electrodynamics (C-QED),metal nanoparticles,fast to slow light,Fano resonance
更新于2025-09-16 10:30:52
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Quantum light-matter interaction and controlled phonon scattering in a photonic Fano cavity
摘要： By using a Fano resonance as one of the mirrors in an optical cavity, a localized mode with a highly asymmetric line shape is obtained. Placing a single quantum emitter inside the cavity leads to a new regime of cavity quantum electrodynamics, where the light-matter interaction dynamics is fundamentally different from that observed in a conventional cavity with Lorenztian line shape. Furthermore, when the vibrational dynamics of the emitter is taken into account, an intricate phonon-photon interplay arises, and the optical interference induced by the Fano mirror signi?cantly alters the leakage of energy into vibrational modes. We demonstrate that this control mechanism improves the maximum attainable indistinguishability of emitted photons, as compared to an equivalent cavity with a conventional mirror.
关键词： phonon scattering,Quantum light-matter interaction,Fano cavity,photonic Fano cavity,cavity quantum electrodynamics
更新于2025-09-12 10:27:22
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Cavity quantum-electrodynamical polaritonically enhanced electron-phonon coupling and its influence on superconductivity
摘要： So far, laser control of solids has been mainly discussed in the context of strong classical nonlinear light-matter coupling in a pump-probe framework. Here, we propose a quantum-electrodynamical setting to address the coupling of a low-dimensional quantum material to quantized electromagnetic fields in quantum cavities. Using a prototypical model system describing FeSe/SrTiO3 with electron-phonon long-range forward scattering, we study how the formation of phonon polaritons at the two-dimensional interface of the material modifies effective couplings and superconducting properties in a Migdal-Eliashberg simulation. We find that through highly polarizable dipolar phonons, large cavity-enhanced electron-phonon couplings are possible, but superconductivity is not enhanced for the forward-scattering pairing mechanism due to the interplay between coupling enhancement and mode softening. Our results demonstrate that quantum cavities enable the engineering of fundamental couplings in solids, paving the way for unprecedented control of material properties.
关键词： phonon polaritons,electron-phonon coupling,superconductivity,cavity quantum electrodynamics,quantum materials
更新于2025-09-10 09:29:36