We investigate the thermodynamics of a combined Dicke- and Ising-model which exhibits a rich phenomenology arising from the second order and quantum phase transitions from the respective models. The partition function is calculated using mean field theory, and the free energy is analyzed in detail to determine the complete phase diagram for the system. The analysis reveals both first- and second-order Dicke phase transitions into a super-radiant state, and the cavity mean-field in this regime acts as an effective magnetic field, which restricts the Ising chain dynamics to parameter ranges away from the Ising phase transition. Physical systems with a first order phase transitions are natural candidates for metrology and calibration purposes, and we apply filter theory to show that the sensitivity of the physical system to temperature and external fields reaches the 1/N Heisenberg limit.
We have analyzed the quadrature squeezing in a cavity mode driven by coherent light and interacting with a two-level atom. We have found that the cavity mode is in a squeezed state, with the maximum quadrature squeezing being $50\%$ below the vacuum-state level. We have also considered the superposition of a pair of cavity modes, each driven by coherent light and interacting with a two-level atom. We have found that the superposed cavity modes are in a squeezed state and the squeezing occurs in both quadratures. We have established that the uncertainty relation perfectly holds for this case. I…
Dynamics of N bodies interacting with quantum cavity is presented. The rotating frame approximation is not used and obtained solutions are the most basic in the framework of generalized Jaynes-Cummings tight-binding model. All presented solutions are entirely analytical and are expressed in terms of elementary functions. Presented scheme can easily be generalized into N bodies (qubits) with M energetic levels interacting with quantum electromagnetic cavity with K energetic levels. Presented framework can be used for construction of software modeling quantum communication between semi-conductor…
We have obtained the commutation relation for a cavity mode driven by coherent light and interacting with a two-level atom. We have found that the commutation relation for a free cavity mode with or without photons is just the usual commutation relation. However, the commutation relation for a cavity mode, which is interacting with a two-level atom, turns out to be different from the usual one.
We theoretically study the dynamical Casimir effect (DCE), i.e., parametric amplification of a quantum vacuum, in an optomechanical cavity interacting with a photonic crystal, which is considered to be an ideal system to study the microscopic dissipation effect on the DCE. Starting from a total Hamiltonian including the photonic band system as well as the optomechanical cavity, we have derived an effective Floquet-Liouvillian by applying the Floquet method and Brillouin-Wigner-Feshbach projection method. The microscopic dissipation effect is rigorously taken into account in terms of the energy…
In this paper, we identify a many-particle phonon expectation value $ζ$ with the ability to induce collective dynamics in a non-interacting atomic gas inside an optical cavity. We then propose to utilise this expectation value to enhance the laser cooling of many atoms through a cyclic two-stage process which consists of cooling and displacement stages. During cooling stages, short laser pulses are applied. These use $ζ$ as a resource and decrease the vibrational energy of the atomic gas by a fixed amount. Subsequent displacement stages use the asymmetry of the trapping potential to replenish …
In this paper we address the analytical solution of the non-resonant interaction between two identical V-type three-level atoms passing consecutively through a single-mode cavity field in the presence of intensity-dependent coupling. By considering an identical initial condition for both atoms and an initial coherent field, we find the analytical solution of the state vector of the entire atom-field system. Accordingly, we could carefully investigate the influence of various parameters in the circumstances of the interacting system on different physical quantities such as the atomic population…
Dynamics of two interacting dipolar two-level systems in a multi-mode electromagnetic cavity: sudden death and revival of the entanglement within the Born-Markov approximation
École Normale Supérieure Paris-Saclay（巴黎萨克雷高等师范学院）；The University of Tokyo（东京大学）
Entanglement dynamics and position-momentum entropic uncertainty relation of a $Λ$-type three-level atom interacting with a two-mode cavity field in the presence of nonlinearities
In the paper, we employ a wavefunction approach to investigate the evolution of a two-photon wave packet propagating in a one-dimensional waveguide coupled to the Jaynes-Cummings (JC) system. We derive and solve, both analytically and numerically, a set of equations of motion governing the quantum state of the system. That allows us to provide real-time analysis of the evolution of the wave packet two-photon joint spectrum (2PJS) and the excitation dynamics of the JC system in the course of its interaction with the two-photon pulse. We demonstrate that the 2PJS and the spectrum of the wave pac…
A cold atomic gas with an inverted population on a transition coupled to a field mode of an optical resonator constitutes a generic model of a laser. For quasi-continuous operation, external pumping, trapping and cooling of the atoms is required to confine them in order to achieve enough gain inside the resonator. As inverted atoms are high-field seekers in blue detuned light fields, tuning the cavity mode to the blue side of the atomic gain transition allows for combining lasing with stimulated cavity cooling and dipole trapping of the atoms at the antinodes of the laser field. We study such …
Comprehending the connections between the geometric, topological, and dynamical structures of integrable quantum systems with quantum phenomena exploitable in quantum information tasks, such as quantum entanglement, is a major problem in geometric information science. In this work we investigate these issues in a physical system of $\mathcal{N}$ interacting spin-$\mathtt{s}$ under long-range Ising model. We discover the relevant dynamics, identify the corresponding quantum phase space and we derive the associated Fubini-Study metric. Through the application of the Gauss-Bonnet theorem and the …
An exact analytic solution for two two-level atoms coupled with a multi-photon single-mode electromagnetic cavity field in the presence of the Stark shift is derived. We assume that the field is initially prepared in a coherent state and the two atoms are initially prepared in an excited state. Considering the atomic level shifts generated by the Stark shift effect, the dynamical behavior of both quantum coherence (QC) measured using a quantum Jensen-Shannon divergence and of quantum correlations captured by quantum discord (QD) are investigated. It is shown that the intensity-dependent Stark-…
Dissipation-induced superradiance in matter coupled to a self-interacting cavity
Institute for Theoretical Physics, ETH Zurich（苏黎世联邦理工学院理论物理研究所）；Department of Physics, University of Strathclyde（斯特拉斯克莱德大学物理系）；Department of Physics, University of Konstanz（康斯坦茨大学物理系）；Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid（马德里自治大学凝聚态物质理论物理系及凝聚态物理中心）
Dynamics of entropy and nonclassical properties of the state of a $Λ$-type three-level atom interacting with a single-mode cavity field with intensity-dependent coupling in a Kerr medium
