Anna Jamroz
We consider spontaneous emission of two two-level atoms interacting with vacuum fluctuations. We study the process of disentanglement in this system and show the possibility of changing disentanglement time by local operations.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
Spontaneous disentanglement and thermalisation
通过在量子动力学中引入引发自发解纠缠与热化的非线性修正主方程，本文发现该非线性项能产生标准量子力学禁止的极限环稳态，其实验观测可为自发解纠缠假设提供重要证据。
Two recent experiments studying the potential effect of entanglement on the emission properties of excited atoms produced in molecular photodissociation have been interpreted in conflicting ways. We present a theoretical analysis of the problem, showing that the experimental results can be explained by a combination of three processes: entanglement, exchange effects associated with the identical nature of the atoms and disentanglement by spontaneous emission. According to our approach these experiments provide the first verification of the phenomenon of disentanglement by spontaneous emission.
The spontaneous disentanglement hypothesis and causality
本文提出基于最大熵原理的假说，通过拉格朗日乘数法确保与因果性一致，适用于有限维希尔伯特空间的量子系统。
We show that under the influence of pure vacuum noise two entangled qubits become completely disentangled in a finite time, and in a specific example we find the time to be given by $\ln \Big(\frac{2 +\sqrt 2}{2}\Big)$ times the usual spontaneous lifetime.
Spontaneous disentanglement of indistinguishable particles
本研究提出适用于不可区分粒子的修正主方程，在玻色-哈伯德和费米-哈伯德模型中，发现退纠缠可引发量子相变。
The 'disentanglement eraser' or 'entanglement restorer' scheme allows retrieving entanglement by erasing the information about the formation of a classical (or separable) state. It suggests an analogy between the pairs of properties: entangled-separable and wave-particle, the latter as described in the 'quantum eraser'. The scheme illustrates the physical importance of information in quantum systems, and it is also useful as a building block for quantum computation. An optical setup for its simple implementation using three-photon decay in a centro-symmetrical crystal is proposed.
Disentanglement in the macroscopic limit
本研究针对宏观极限，采用具有已知精确解的多体模型，探究自发退纠缠假设，发现非局域纠缠在宏观极限下不稳定、局域纠缠未被排除稳定性，该假设可衔接微观量子性与宏观经典性。
We investigate the nature of quantum entanglement in long-range orders and spontaneous symmetry breaking. It is shown that diminishing of entanglement between the condensate mode and the rest of the system underlies off-diagonal long-range order, which is the hallmark of superconductivity and Bose-Einstein condensation. It is also revealed that disentanglement underlies various cases of long-range order and spontaneous symmetry breaking. In the course of the discussion, we also present some ideas on characterizing entanglement in many-body systems. Especially, it is shown how the connected cor…
Disentanglement--induced bistability in a magnetic resonator
实验发现铁磁自旋谐振器多稳态无法由线性主方程解释，提出解纠缠假设模型，与玻色化方法对比，解纠缠模型更吻合数据，间接支持自发解纠缠假设。
The stability of entanglement of two atoms in a cavity is analyzed in this work. By studying the general Werner states we clarify the role of Bell-singlet state in the problem of suppression of disentanglement due to spontaneous emission. It is also shown explicitly that the final amount of entanglement depends on the initial ingredients of the Bell-singlet state.
Disentanglement-induced multistability
本文研究含解纠缠非线性项的主方程在耦合自旋系统中的动力学，发现该非线性项可诱导多稳态，并通过自旋对外磁场的响应揭示相变与动力学不稳定性，从而间接支持量子系统中存在自发解纠缠的假设。
We present a review of recent research on quantum entanglement, with special emphasis on entanglement between single atoms, processing of an encoded entanglement and its temporary evolution. Analysis based on the density matrix formalism are described. We give a simple description of the entangling procedure and explore the role of the environment in creation of entanglement and in disentanglement of atomic systems. A particular process we will focus on is spontaneous emission, usually recognized as an irreversible loss of information and entanglement encoded in the internal states of the syst…
Disentanglement-induced superconductivity
针对粒子数守恒与超导性的矛盾，提出基于自发退纠缠的替代模型，用费米-哈伯德模型展示退纠缠诱导超导相变，并探讨其对约瑟夫森结的影响。
The dynamics of entanglement between three - level atoms coupled to the common vacuum is investigated. We show that the collective effects such as collective damping, dipole - dipole interaction and the cross coupling between orthogonal dipoles, play a crucial role in the process of creation of entanglement. In particular, the additional cross coupling enhances the production of entanglement. For the specific initial states we find that the effect of delayed sudden birth of entanglement, recently invented by Ficek and Tanas [Phys. Rev. A 77, o54301(2008)] in the case of two - level atoms, can …
We consider a pair of three-level atoms interacting with the vacuum. The process of disentanglement due to spontaneous emission and the role of quantum interference between principal transitions in this process, are analysed. We show that the presence of interference can slow down disentanglement. In the limit of maximal interference, some part of initial entanglement can survive.
We investigate the dynamical behavior of the atom-photon entanglement in a V-type three-level quantum system using the atomic reduced entropy. It is shown that an atom and photons are entangled at the steady-state; however disentanglement can also be achieved in an especial condition. It is demonstrated that in the presence of quantum interference induced by spontaneous emission, the reduced entropy and the atom-photon entanglement are phase-dependent. Non-stationary solution is also obtained when the quantum interference due to the spontaneous emission is completely included.
Disentanglement and loss of quantum correlations due to one global collective noise effect are described for two-qubit Schrödinger cat and Werner states of a four level trapped ion quantum system. Once the Jaynes-Cummings ionic interactions are mapped onto a Dirac spinor structure, the elementary tools for computing quantum correlations of two-qubit ionic states are provided. With two-qubit quantum numbers related to the total angular momentum and to its projection onto the direction of an external magnetic field (which lifts the degeneracy of the ion's internal levels), a complete analytical …
We analyse the influence of entanglement on the emission properties of atoms. To this end, first, we propose a scheme for the preparation of a pair of entangled Helium atoms, one in the ortho and the other in the para spin configuration. We discuss a realistic scenario for this process, based in the double ionization of He by intense laser fields. These states are used to analyse disentanglement and the role of entanglement in the spontaneous emission from the pair. In particular, we show that the decaying rate of an entangled atom is different from that in a product state, modifying the tempo…
Entropic uncertainty and entanglement are two distinct aspects of quantum mechanical procedures. To estimate entropic uncertainty relations, entropies are used: the greater the entropy bound, the less effective the quantum operations and entanglement are. In this regard, we analyze the entropic uncertainty, entropic uncertainty lower bound, and concurrence dynamics in two non-interacting qubits. The exposure of two qubits is studied in two different qubit-noise configurations, namely, common qubit-noise and independent qubit-noise interactions. To include the noisy effects of the local externa…
The density matrix equations of motion in near-degenerate three-level V-type closed-loop atomic system are calculated numerically in Floquet frame. The dynamical behavior of atom- photon entanglement between the dressed atom and its spontaneous emission is studied in semi classical approach beyond the two-photon resonance condition in such a system. The quantum entropy of these two subsystems is investigated by using the von Neumann entropy. It is shown that, the degree of entanglement measure (DEM) can be controlled via the intensity and the detuning of coupling optical field and quantum inte…
Graviton absorption cross sections and emission rates for hydrogen are calculated by both semi-classical and field theoretic methods. We point out several mistakes in the literature concerning spontaneous emission of gravitons and related phenomena, some of which are due to a subtle issue concerning gauge invariance of the linearized interaction Hamiltonian.
The dynamics of an electronic two-level system coupled to an electromagnetic field are simulated explicitly for one and three dimensional systems through semiclassical propagation of the Maxwell-Liouville equations. We consider three flavors of mixed quantum-classical dynamics: the classical path approximation (CPA), Ehrenfest dynamics, and symmetrical quantum-classical (SQC) dynamics. The CPA fails to recover a consistent description of spontaneous emission. A consistent "spontaneous" emission can be obtained from Ehrenfest dynamics--provided that one starts in an electronic superposition sta…
We theoretically investigate the effect of dissipation on multi-photon excitation of Rydberg atoms. The steady states and the dynamics are compared via two types of four-level excitation schemes with different dissipative paths of spontaneous emission. We find that in the case of strong Rydberg-Rydberg interaction, the schemes will settle in several different non-equilibrium steady states. The interesting aspect is that there exists the multi-stable steady states, which reveals the competition between interaction-induced nonlinearity and dissipation caused by spontaneous emission. A numerical …
Directional spontaneous emission in photonic crystal slabs
本文研究光子晶体平板中定向自发辐射与几何参数、发射体位置及偏振的关系，揭示通过实际材料结构精细调控集体量子光学现象的潜力。
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。