The Evolution Operator of The Three Atoms Tavis-Cummings Model

Algebraic approach to the Tavis-Cummings model with three modes of oscillation

We study the Tavis-Cummings model with three modes of oscillation by using four different algebraic methods: the Bogoliubov transformation, the normal-mode operators, and the tilting transformation of the $SU(1,1)$ and $SU(2)$ groups. The algebraic method based on the Bogoliubov transformation and the normal-mode operators let us obtain the energy spectrum and eigenfunctions of a particular case of the Tavis-Cummings model, while with the tilting transformation we are able to solve the most general case of this Hamiltonian. Finally, we compute some expectation values of this problem by means o…

An algebraic approach to the Tavis-Cummings problem

An algebraic method is introduced for an analytical solution of the eigenvalue problem of the Tavis-Cummings (TC) Hamiltonian, based on polynomially deformed su(2), i.e. su_n(2), algebras. In this method the eigenvalue problem is solved in terms of a specific perturbation theory, developed here up to third order. Generalization to the N-atom case of the Rabi frequency and dressed states is also provided. A remarkable enhancement of spontaneous emission of N atoms in a resonator is found to result from collective effects.

Tavis-Cummings系统中光子阻塞的观察

Observation of Photon Blockade in a Tavis-Cummings System

本文在包含超导腔与最多3个transmon量子比特的Tavis-Cummings系统中观察到了微波光子阻塞，并利用光子数分辨光谱学证实了极化激元形成及亚泊松光子统计。

Berry phase of the Tavis-Cummings model with three modes of oscillation

In this paper we develop a general method to obtain the Berry phase of time-dependent Hamiltonians with a linear structure given in terms of the $SU(1,1)$ and $SU(2)$ groups. This method is based on the similarity transformations of the displacement operator performed to the generators of each group, and let us diagonalize these Hamiltonians. Then, we introduce a trilinear form of the Tavis-Cummings model to compute the $SU(1,1)$ and $SU(2)$ Berry phases of this model.

Entanglement dynamics for the double Tavis-Cummings model

A double Tavis-Cummings model (DTCM) is developed to simulate the entanglement dynamics of realistic quantum information processing where two entangled atom-pairs $AB$ and $CD$ are distributed in such a way that atoms $AC$ are embedded in a cavity $a$ while $BD$ are located in another remote cavity $b$. The evolutions of different types of initially shared entanglement of atoms are studied under various initial states of cavity fields. The results obtained in the DTCM are compared with that obtained in the double Jaynes-Cummings model (DJCM) [J. Phys. B \textbf{40}, S45 (2007)] and an interact…

Thermal entanglement and efficiency of the quantum Otto cycle for the su(1,1) Tavis-Cummings system

The influence of the dynamical Stark shift on the thermal entanglement and the efficiency of the quantum Otto cycle is studied for the su(1,1) Tavis-Cummings system. It is shown that the degree of the thermal entanglement becomes larger as the dynamical Stark shift increases. In contrast, the efficiency of the Otto cycle is degraded with an increase of the values of dynamical Stark shift. Expressions for the efficiency coefficient are derived. Using those expressions we identify the maximal efficiency of the quantum Otto cycle from the experimentally measured values of the dynamical Stark shif…

Beyond the Tavis-Cummings model: revisiting cavity QED with atomic ensembles

The interaction of an ensemble of $N$ two-level atoms with a single mode electromagnetic field is described by the Tavis-Cummings model. There, the collectively enhanced light-matter coupling strength is given by $g_N = \sqrt{N} \bar{g}_1$, where $\bar{g}_1$ is the ensemble-averaged single-atom coupling strength. Formerly, this model has been employed to describe and to analyze numerous cavity-based experiments. Here, we show that this is only justified if the effective scattering rate into non-cavity modes is negligible compared to the cavity's free-spectral range. In terms of experimental pa…

The influence of dipole-dipole interaction on entanglement in nondegenerate two-photon Tavis-Cummings model with atomic coherence

The entanglement of two dipole-coupled atoms with nondegenerate two-photon transitions interacting with two-mode field in lossless cavity has been investigated. It shows that the entanglement is dependent on the initial atomic states. The possibility of considerable growth of atomic entanglement due atomic coherence and dipole-dipole interaction is shown in the case of great mean values of thermal photons.

Collective Effects of Organic Molecules based on Holstein-Tavis-Cummings Model

We study the collective effects of an ensemble of organic molecules confined in an optical cavity based on Holstein-Tavis-Cummings model. By using the quantum Langevin approach and adiabatically eliminating the degree of freedom of the vibrational motion, we analytically obtain the expression of the cavity transmission spectrum to analyze the features of polaritonic states. As an application, we show that the dependence for the frequency shift of the lower polaritonic state on the number of molecules can be used in the detection of the ultra-cold molecules. We also numerically analyze the fluo…

Strong coupling optical spectra in dipole-dipole interacting optomechanical Tavis-Cummings models

We theoretically investigate the emission spectrum of an optomechanical Tavis-Cummings model: two dipole-dipole interacting atoms coupled to an optomechanical cavity (OMC). In particular, we study the influence of dipole-dipole interaction (DDI) on the single-photon spectrum emitted by this hybrid system in the presence of a strong atom-cavity as well as strong optomechanical interaction (hereinafter called the strong-strong coupling). We also show that our analysis is amenable to inclusion of mechanical losses (under the weak mechanical damping limit) and single-photon loss through spontaneou…

Optical nonreciprocal response and conversion in a Tavis-Cummings coupling optomechanical system

We propose a scheme to realize optical nonreciprocal response and conversion in a Tavis-Cummings coupling optomechanical system, where a single cavity mode interacts with the vibrational mode of a flexible membrane with an embedded ensemble of two-level quantum emitters. Due to the introduction of the Tavis-Cummings interaction, we find that the phases between the mechanical mode and the optical mode, as well as between the mechanical mode and the dopant mode, are correlated with each other, and further give the analytical relationship between them. By optimizing the system parameters, especia…

Two Qubits Tavis-Cummings Model Beyond the Rotating Wave Approximation: Degenerate Regime

We study the dynamics of two qubits interacting with a single mode of a harmonic oscillator beyond the rotating wave approximation in the ideally degenerate regime. Exact analytic expressions are obtained for state properties of interest, including qubit entanglement for a certain class of initial states of the oscillator and the qubits. Qualitative differences and similarities in the evolution of the qubits in the degenerate regime when the oscillator is treated quantum mechanically and classically are discussed.

不同量子信道下Tavis-Cummings模型的准概率分布研究

A study of the quasi-probability distributions of the Tavis-Cummings model under different quantum channels

本文利用准概率分布和二阶相干函数研究了Tavis-Cummings模型在不同量子信道下的自旋与腔场动力学，揭示了噪声对光子数、自旋激发及腔辐射聚束特性的影响。

Superradiance in dynamically modulated Tavis-Cumming model with spectral disorder

Superradiance is the enhanced emission of photons from quantum emitters collectively coupling to the same optical mode. However, disorder in the resonant frequencies of the quantum emitters can perturb this effect. In this paper, we study the interplay between superradiance and spectral disorder in a dynamically modulated Tavis-Cummings model. Through numerical simulations and analytical calculations, we show that the effective cooperativity of the superradiant mode, which is always formed over an extensive number of emitters, can be multiplicatively enhanced with a quantum control protocol mo…

Measurement-induced chaos and quantum state discrimination in an iterated Tavis-Cummings scheme

A cavity quantum electrodynamical scenario is proposed for implementing a Schrödinger microscope capable of amplifying differences between non orthogonal atomic quantum states. The scheme involves an ensemble of identically prepared two-level atoms interacting pairwise with a single mode of the radiation field as described by the Tavis-Cummings model. By repeated measurements of the cavity field and of one atom within each pair a measurement-induced nonlinear quantum transformation of the relevant atomic states can be realized. The intricate dynamical properties of this nonlinear quantum trans…

Quality of Control in the Tavis-Cummings-Hubbard Model

The quality of controlling a system of optical cavities in the Tavis-Cummings-Hubbard (TCH) model is estimated with the examples of quantum gates, quantum walks on graphs, and of the detection of singlet states. This type of control of complex systems is important for quantum computing, for the optical interpretation of mechanical movements, and for quantum cryptography, where singlet states of photons and charges play an essential role. It has been found that the main reason for the decrease of the control quality in the THC model is due to the finite width of the atomic spectral lines, which…

Analytic Approximation of the Tavis-Cummings Ground State via Projected States

We show that an excellent approximation to the exact quantum solution of the ground state of the Tavis-Cummings model is obtained by means of a semi-classical projected state. This state has an analytical form in terms of the model parameters and, in contrast to the exact quantum state, it allows for an analytical calculation of the expectation values of field and matter observables, entanglement entropy between field and matter, squeezing parameter, and population probability distributions. The fidelity between this projected state and the exact quantum ground state is very close to 1, except…

The entanglement character between atoms in the non-degenerate two photons Tavis-Cummings model

The entanglement character including the so-called sudden death effect between atoms in the non-degenerate two photons Tavis-Cummings model is studied by means of concurrence. The results show that the so-called sudden death effect occurs only for some kind of initial states. In other words, the phenomenon is sensitive to the initial conditions. One can expect the resurrection of the original entanglement to occur in a periodic way following each sudden death event. The length of the time interval for the zero entanglement is dependent on not only the degree of entanglement of the initial stat…

Entanglement Sharing in the Two-Atom Tavis-Cummings Model

Individual members of an ensemble of identical systems coupled to a common probe can become entangled with one another, even when they do not interact directly. We investigate how this type of multipartite entanglement is generated in the context of a system consisting of two two-level atoms resonantly coupled to a single mode of the electromagnetic field. The dynamical evolution is studied in terms of the entanglements in the different bipartite partitions of the system, as quantified by the I-tangle. We also propose a generalization of the so-called residual tangle that quantifies the inhere…

Entanglement in the adiabatic limit of a two-atom Tavis-Cummings model

We study the adiabatic limit for the sequential passage of atoms through a high-Q cavity, in the presence of frequency chirps. Despite the fact that the adiabatic approximation might be expected to fail, we were able to show that for proper choice of Stark-pulses this is not the case. Instead, a connection to the resonant limit is established, where the robust creation of entanglement is demonstrated. Recent developments in the fabrication of high-Q cavities allow fidelities for a maximally entangled state up to 97%.

Explicit Form of the Evolution Operator for the Four Atoms Tavis-Cummings Model

In this letter the explicit form of evolution operator for the four atoms Tavis-Cummings model is given.

通过驱动的Tavis-Cummings模型工程化近单位元一轴扭曲演化

Engineering near-unitary one-axis twisting evolution via a driven Tavis-Cummings model

本文通过驱动的Tavis-Cummings模型实现近单位元一轴扭曲演化，克服了传统方法中光-原子纠缠导致的单位性破坏问题，并在不同驱动条件下提升了OAT演化精度与抗退相干能力。

Explicit Form of Evolution Operator of Three Atoms Tavis-Cummings Model

In this letter the explicit form of evolution operator of three atoms Tavis-Cummings model is given, which is a generalization of the paper quant-ph/0403008.

参数驱动Tavis-Cummings模型的量子度量与计量学

Quantum metric and metrology with parametrically-driven Tavis-Cummings models

本研究针对参数驱动的Tavis-Cummings模型，解析求解本征态并数值模拟临界行为，用量子度量表征超辐射相变临界特性，提出基于该临界行为的量子计量方案以提升测量精度。

Coherent Perfect Absorption in Tavis-Cummings Models

We theoretically study the conditions under which two laser fields can undergo Coherent Perfect Absorption (CPA) when shined on a single-mode bi-directional optical cavity coupled with two two- level quantum emitters (natural atoms, artificial atoms, quantum dots, qubits, etc.). In addition to being indirectly coupled through the cavity-mediated field, in our Tavis-Cummings model the two quantum emitters (QEs) are allowed to interact directly via the dipole-dipole interaction (DDI). Under the mean-field approximation and low-excitation assumption, in this work, we particularly focus on the imp…

On the Dynamics of the Tavis-Cummings Model

The purpose of this paper is to present a comprehensive study of the Tavis-Cummings model from a system-theoretic perspective. A typical form of the Tavis-Cummings model is composed of an ensemble of non-interacting two-level systems (TLSs) that are collectively coupled to a common cavity resonator. The associated quantum linear passive system is proposed, whose canonical form reveals typical features of the Tavis-Cummings model, including $\sqrt{N}$- scaling, dark states, bright states, single-excitation superradiant and subradiant states. The passivity of this linear system is related to the…

Experimentally Accessible Quantum Phase Transition in a non-Hermitian Tavis-Cummings Model Engineered with Two Drive Fields

We study the quantum phase transition (QPT) in a non-Hermitian Tavis-Cummings (TC) model of experimentally accessible parameters, which is engineered with two drive fields applied to an ensemble of two-level systems (TLSs) and a cavity, respectively. When the two drive fields satisfy a given parameter-matching condition, the coupled cavity-TLS ensemble system can be described by an effective standard TC Hamiltonian in the rotating frame. In this ideal Hermitian case, the engineered TC model can exhibit the super-radiant QPT with spin conservation at an experimentally accessible critical coupli…

在Tavis-Cummings模型中逼近双重海森堡标度灵敏度

Approaching the double-Heisenberg scaling sensitivity in the Tavis-Cummings model

本文证明Tavis-Cummings模型借助相干平均机制可在平均光子数和原子数上同时实现双重海森堡标度灵敏度，并通过量子压缩在实验上实现，为腔QED和超导电路提供计量应用。

广义 Tavis-Cummings 模型中由 $XY$ 自旋相互作用增强的量子计量

Quantum metrology enhanced by the $XY$ spin interaction in a generalized Tavis-Cummings model

提出含 $XY$ 自旋相互作用的广义 Tavis-Cummings 模型，建立 QFI 与自旋涨落的关系，证明自旋各向异性可实现弱磁场估计的 Heisenberg 标度并揭示标度转变。

在Tavis-Cummings模型中纯态与混合态纠缠动力学的研究

Pure and Mixed State Entanglement Dynamics in Tavis-Cummings Model with Squeezed Coherent Thermal States

研究在Tavis-Cummings模型中，通过纯态和混合态的纠缠动力学比较，探讨压缩相干热态对纠缠行为的影响。

Entangling operations in nonlinear two-atom Tavis-Cummings models

We derive an analytical approximate solution of the time-dependent state vector in terms of material Bell states and coherent states of the field for a generalized two-atom Tavis-Cummings model with nonlinear intensity dependent matter-field interaction. Using this solution, we obtain simple expressions for the atomic concurrence and purity in order to study the entanglement in the system at specific interaction times. We show how to implement entangling atomic operations through measurement of the field. We illustrate how these operations can lead to a complete Bell measurement. Furthermore, …

用于含时酉Tavis-Cummings模型的辛分裂算子方法

Symplectic split-operator method for the time-dependent unitary Tavis-Cummings model

本文提出一种超越旋波近似的辛分裂算子方法，可高效模拟含时酉Tavis-Cummings模型，计算复杂度与系统总维数呈线性关系，适用于哈密顿项可转化为三对角形式的闭合量子系统模拟。

Tavis-Cummings model beyond the rotating wave approximation: Quasi-degenerate qubits

The Tavis-Cummings model for more than one qubit interacting with a common oscillator mode is extended beyond the rotating wave approximation (RWA). We explore the parameter regime in which the frequencies of the qubits are much smaller than the oscillator frequency and the coupling strength is allowed to be ultra-strong. The application of the adiabatic approximation, introduced by Irish, et al. (Phys. Rev. B \textbf{72}, 195410 (2005)), for a single qubit system is extended to the multi-qubit case. For a two-qubit system, we identify three-state manifolds of close-lying dressed energy levels…

Tavis-Cummings models and their quasi-exactly solvable Schrödinger Hamiltonians

We study in detail the relationship between the Tavis-Cummings Hamiltonian of quantum optics and a family of quasi-exactly solvable Schrödinger equations. The connection between them is stablished through the biconfluent Heun equation. We found that each invariant $n$-dimensional subspace of Tavis-Cummings Hamiltonian corresponds either to $n$ potentials, each with one known solution, or to one potential with $n$-known solutions. Among these Schrödinger potentials appear the quarkonium and the sextic oscillator.

Exploring the quantum critical behaviour in a driven Tavis-Cummings circuit

Quantum phase transitions play an important role in many-body systems and have been a research focus in conventional condensed matter physics over the past few decades. Artificial atoms, such as superconducting qubits that can be individually manipulated, provide a new paradigm of realising and exploring quantum phase transitions by engineering an on-chip quantum simulator. Here we demonstrate experimentally the quantum critical behaviour in a highly-controllable superconducting circuit, consisting of four qubits coupled to a common resonator mode. By off-resonantly driving the system to renor…

Coherent State Description of the Ground State in the Tavis-Cummings Model and its Quantum Phase Transitions

Quantum phase transitions and observables of interest of the ground state in the Tavis-Cummings model are analyzed, for any number of atoms, by using a tensorial product of coherent states. It is found that this "trial" state constitutes a very good approximation to the exact quantum solution, in that it globally reproduces the expectation values of the matter and field observables. These include the population and dipole moments of the two-level atoms and the squeezing parameter. Agreement in the field-matter entanglement and in the fidelity measures, of interest in quantum information theory…

What can we learn from the dynamics of entanglement and quantum discord in the Tavis-Cummings model?

We revisit the problem of the dynamics of quantum correlations in the exact Tavis-Cummings model. We show that many of the dynamical features of quantum discord attributed to dissipation are already present in the exact framework and are due to the well known non-linearities in the model and to the choice of initial conditions. Through a comprehensive analysis, supported by explicit analytical calculations, we find that the dynamics of entanglement and quantum discord are far from being trivial or intuitive. In this context, we find states that are indistinguishable from the point of view of e…

Exact Results for the Tavis-Cummings and H$\boldsymbol{\ddot{u}}$ckel Hamiltonians with Diagonal Disorder

We present an exact method to calculate the electronic states of one electron Hamiltonians with diagonal disorder. We show that the disorder averaged one particle Green's function can be calculated directly, using a deterministic complex (non-Hermitian) Hamiltonian. For this, we assume that the molecular states have a Cauchy (Lorentz) distribution and use the supersymmetric method which has already been used in problems of solid state physics. Using the method we find exact solutions to the states of $N$ molecules, confined to a microcavity, for any value of $N$. Our analysis shows that the wi…

分子Tavis-Cummings模型中退相位对暗态耦合的作用

The role of dephasing for dark state coupling in a molecular Tavis-Cummings model

本研究针对分子Tavis-Cummings模型中暗态难以被光学访问的问题，通过含纯退相位与光子衰减的Lindblad方程建模，发现退相位速率和粒子数对暗态布居有显著影响。

High Jaynes-Cummings pseudospins eigenstates in the homogeneous Tavis-Cummings model

We show that a set of N identical qubits coupled to a single cavity resonator can be decomposed into a set of independent subsystems, which can be thought of as higher pseudospin generalisations of the Jaynes-Cummings model. We derive and analyse the solutions to the equations of motion and demonstrate unusual beating behaviour resulting from a new form of square-root-n-type non-linearity appearing within a pseudospin ladder. Furthermore, we propose a relative phase shift transformation which allows one to switch/initiate the multi-qubit state in a desired pseudospin configuration, and show ho…

使用改进版Tavis-Cummings-Hubbard模型模拟中性氢分子的形成

Using a modified version of the Tavis-Cummings-Hubbard model to simulate the formation of neutral hydrogen molecule

本文提出用改进的Tavis-Cummings-Hubbard模型模拟中性氢分子形成，通过量子主方程描述原子核运动、轨道杂化和自旋跃迁，并分析光子模式温度效应，进而提出含共价键与声子的更精确模型。

混沌Tavis-Cummings模型中的热化 regime

Thermalization Regimes in a Chaotic Tavis-Cummings Model

研究混沌Tavis-Cummings模型中的热化现象及其对量子光谱学的影响，通过量子混沌和厄尔戈迪city探讨多体效应和输出光子统计特性。

用随机轨迹建模多体量子动力学：对Tavis-Cummings模型的关键测试

Modelling many-body quantum dynamics with stochastic trajectories: a critical test on the Tavis-Cummings model

本研究将随机轨迹采样框架应用于Tavis-Cummings模型，发现其解存在发散性，限制了适用时间，转换SDEs可推延有效时间边界，但仍无法恢复量子坍缩和复兴，揭示该方法在强量子特征系统中的普遍困难。

Tavis-Cummings量子电池中的最优能量存储

Optimal energy storage in the Tavis-Cummings quantum battery

本研究针对Tavis-Cummings量子电池模型，引入不变子空间方法表征其量子动力学，揭示了SU(2)对称性与最优储能的关联、纠缠与储能的负相关，证明了大尺度下的渐近最优储能，丰富了量子电池理论。

Explicit Form of the Evolution Operator of Tavis-Cummings Model : Three and Four Atoms Cases

In this letter the explicit form of evolution operator of the Tavis-Cummings model with three and four atoms is given. This is an important progress in quantum optics or mathematical physics.

Tavis-Cummings model beyond the rotating wave approximation: Inhomogeneous coupling

We present the analytical solution of the Tavis-Cummings (TC) model for more than one qubit inhomogeneously coupled to a single mode radiation field beyond the rotating-wave approximation (RWA). The significant advantage of the displaced oscillator basis enables us to apply the same truncation techniques adopted in the single qubit Jaynes-Cummings (JC) model to the multiple qubits system. The derived analytical spectrum match perfectly the exact diagonalization numerical solutions of the inhomogeneous TC model in the parameter regime where the qubits transition frequencies are far off-resonanc…

具有XY自旋相互作用的广义Tavis-Cummings模型中的动力学多体纠缠

Dynamical multipartite entanglement in a generalized Tavis-Cummings model with XY spin interaction

本文研究引入XY自旋相互作用的广义Tavis-Cummings模型中的动力学多体纠缠，通过Holstein-Primakoff变换建立其与中心自旋模型的联系，并揭示强耦合、低温及磁场对纠缠的调控作用。

Dynamics of Entanglement and `Attractor' states in The Tavis-Cummings Model

We study the time evolution of $N_q$ two-level atoms (or qubits) interacting with a single mode of the quantised radiation field. In the case of two qubits, we show that for a set of initial conditions the reduced density matrix of the atomic system approaches that of a pure state at $\sfrac{t_r}{4}$, halfway between that start of the collapse and the first mini revival peak, where $t_r$ is the time of the main revival. The pure state approached is the same for a set of initial conditions and is thus termed an `attractor state'. The set itself is termed the basin of attraction and the features…

Exciton-polarons in two-dimensional semiconductors and the Tavis-Cummings model

The elementary optical excitations of a two-dimensional electron or hole system have been identified as exciton-Fermi-polarons. Nevertheless, the connection between the bound state of an exciton and an electron, termed trion, and exciton-polarons is subject of ongoing debate. Here, we use an analogy to the Tavis-Cummings model of quantum optics to show that an exciton-polaron can be understood as a hybrid quasiparticle -- a coherent superposition of a bare exciton in an unperturbed Fermi sea and a bright collective excitation of many trions. The analogy is valid to the extent that the Chevy An…

Optimal state for a Tavis-Cummings quantum battery via the Bethe ansatz method

In this paper, we investigate the effect of different optical field initial states on the performance of the Tavis-Cummings (T-C) quantum battery. In solving the dynamical evolution of the system, we found a fast way to solve the Bethe ansatz equation. We find that the stored energy and the average charging power of the T-C quantum battery are closely related to the probability distribution of the optical field initial state in the number states. We define a quantity called the number-state stored energy. With this prescribed quantity, we only need to know the probability distribution of the o…

Landau-Zener extension of the Tavis-Cummings model: structure of the solution

We explore the recently discovered solution of the driven Tavis-Cummings model (DTCM). It describes interaction of arbitrary number of two-level systems with a bosonic mode that has linearly time-dependent frequency. We derive compact and tractable expressions for transition probabilities in terms of the well known special functions. In the new form, our formulas are suitable for fast numerical calculations and analytical approximations. As an application, we obtain the semiclassical limit of the exact solution and compare it to prior approximations. We also reveal connection between DTCM and …

Tavis-Cummings模型中暗态的坍缩

Collapse of dark states in Tavis-Cummings model

本文研究了Tavis-Cummings模型中原子单重态暗态在哈密顿量缓慢形变下的坍缩行为，发现存在不依赖形变平滑度的光子发射，并分析了原子数变化及双腔情形对该量子效应的影响，论证了暗态在量子信息与纳米器件中的应用前景。

Dissipative Two-Mode Tavis-Cummings Model with Time-Delayed Feedback Control

We investigate the dynamics of a two-mode laser system by extending the two-mode Tavis-Cummings model with dissipative channels and incoherent pumping and by applying the mean-field approximation in the thermodynamic limit. To this end we analytically calculate up to four possible non-equilibrium steady states (fixed points) and determine the corresponding complex phase diagram. Various possible phases are distinguished by the actual number of fixed points and their stability. In addition, we apply three time-delayed Pyragas feedback control schemes. Depending on the time delay and the strengt…

Non-equilibrium dynamics of the Tavis-Cummings model

In quantum many-body theory no generic microscopic principle at the origin of complex dynamics is known. Quite opposed, in classical mechanics the theory of non-linear dynamics provides a detailed framework for the distinction between near-integrable and chaotic systems. Here we propose to describe the off-equilibrium dynamics of the Tavis-Cummings model by an underlying classical Hamiltonian system, which can be analyzed using the powerful tools of classical theory of motion. We show that scattering in the classical phase space can drive the quantum model close to thermal equilibrium. Interes…