我们将我们的方法推广到吸收介质多层膜之间的Casimir效应[M. S. Tomas，Phys.Rev.A66，052103（2002）]中描述的方法。所得到的力的表达式是用来数值探讨的吸引力/排斥力的金属磁介电系统中的Drude-Lorentz磁电阻率和磁导率的介质色散的效果。
英文摘要：
We extend our approach to the Casimir effect between absorbing dielectric multilayers [M. S. Tomas, Phys. Rev. A 66, 052103 (2002)] to magnetodielectric systems. The resulting expression for the force is used to numerically explore the effect of the medium dispersion on the attractive/repulsive force in a metal-magnetodielectric system described by the Drude-Lorentz permittivities and permeabilities.
We present a worldline method for the calculation of Casimir energies for scalar fields coupled to magnetodielectric media. The scalar model we consider may be applied in arbitrary geometries, and it corresponds exactly to one polarization of the electromagnetic field in planar layered media. Starting from the field theory for electromagnetism, we work with the two decoupled polarizations in planar media and develop worldline path integrals, which represent the two polarizations separately, for computing both Casimir and Casimir-Polder potentials. We then show analytically that the path integr…
We find the analytic expressions for the Casimir free energy, entropy and pressure at low temperature in the configuration of two parallel plates made of magnetodielectic material. The cases of constant and frequency-dependent dielectic permittivity and magnetic permeability of the plates are considered. Special attention is paid to the account of dc conductivity. It is shown that in the case of finite static dielectric permittivity and magnetic permeability the Nernst heat theorem for the Casimir entropy is satisfied. If the dc conductivity is taken into account, the Casimir entropy goes to a…
Boyer showed that a perfect electrically conducting slab repels a perfect magnetically conducting slab, in contrast to the attractive Casimir force between two identical perfect electrically/magnetically conducting slabs. To gain insight for the difference between the Boyer force and the Casimir force, we present the derivation of the Boyer force using the stress tensor method and then using the method of variation in dielectric. The Green dyadic, in terms of electric and magnetic Green's functions, is presented for an electric medium filling half of space and another magnetic medium filling a…
We develop a dynamical approach to study the Casimir-Polder force between a initially bare molecule and a magnetodielectric body at finite temperature. Switching on the interaction between the molecule and the field at a particular time, we study the resulting temporal evolution of the Casimir-Polder interaction. The dynamical self-dressing of the molecule and its population-induced dynamics are accounted for and discussed. In particular, we find that the Casimir-Polder force between a chiral molecule and a perfect mirror oscillates in time with a frequency related to the molecular transition …
We demonstrate under which conditions a violation of the charge-parity (CP) symmetry in molecules will manifest itself in the Casimir-Polder interaction of these with a magnetodielectric surface. Charge-parity violation induces a specific electric-magnetic cross-polarisability in a molecule that is not chiral, but time-reversal (T) symmetry violating. As we show, a detection of such an effect via the Casimir-Polder potential requires a material medium that is also sensitive to time-reversal, i.e., it must exhibit a non-reciprocal electromagnetic response. As simple examples of such media we co…
我们建立了色散力之间的一般关系。首先，基于因果介质中的QED，采用首阶微扰理论，用原子极化率和体助电磁场的格林张量来表示单原子Casimir-Polder势和双原子van der Waals势。在这个几何无关的框架下，我们采用格林张量的玻恩展开和Clausius-Mosotti关系，证明了在介电体存在下，原子的宏观Casimir-Polder势是由其微观多原子与组成介电体的原子之间的范德华相互作用的无穷和所引起的.这个定理适用于非均匀的，分散的，和吸收机构的任意形状和任意原子组成的任意背景下的附加磁介电体。
In this paper, we theoretically propose and investigate a feasible experimental scheme for realizing the dynamical Casimir effect (DCE) of phonons in an optomechanical setup formed by a ground-state precooled mechanical oscillator (MO) inside a Fabry-P{é}rot cavity, which is driven by an amplitude-modulated classical laser field in the dispersive (far-detuned) regime. The time modulation of the driving field leads to the parametric amplification of the mechanical vacuum fluctuations of the MO, which results in the generation of Casimir phonons over time scales longer than the cavity lifetime. …
The repulsive nature of the static Casimir force between two half-spaces, one perfectly dielectric and the other purely magnetic, has been known since Boyer's work [T. H. Boyer, Phys. Rev. A {\bf 9}, 2078 (1974)]. We here analyze the corresponding friction force in the magnetodielectric case. Our main method is that of quantum mechanical statistical mechanics. The basic model we introduce is a harmonic oscillator model: an electric dipole oscillating in the $x$ direction and a magnetic one oscillating in the $y$ direction, while their separation is in the $z$ direction. This is then extended t…
We consider the nonstationary circuit QED setup in which a 3-level artificial atom in the $Δ$-configuration interacts with a single-mode cavity field of natural frequency $ω$. It is demonstrated that when some atomic energy level(s) undergoes a weak harmonic modulation, photons can be generated from vacuum via effective 1- and 3-photon transitions, while the atom remains approximately in the ground state. These phenomena occur in the dispersive regime when the modulation frequency is accurately tuned near $ω$ and $3ω$, respectively, and the generated field states exhibit strikingly different s…
Atom-surface forces using excited states have a host of compelling applications, including repulsive and lateral forces. However, such states can be fragile and difficult to prepare. Here we report an explicit normal-mode based calculation of the Casimir-Polder potential between a ground-state atom and a non-dispersive surface in the presence of an external quantised field. The potential we derive shares some features with that of excited-state Casimir-Polder forces even though we consider a ground-state atom. Our work provides a physically transparent and intuitive picture of driven Casimir-P…
We show that the dynamical Casimir effect in an optomechanical system can be achieved under incoherent mechanical pumping. We adopt a fully quantum-mechanical approach for both the cavity field and the oscillating mirror. The dynamics is then evaluated using a recently-developed master equation approach in the dressed picture, including both zero and finite temperature photonic reservoirs. This analysis shows that the dynamical Casimir effect can be observed even when the mean value of the mechanical displacement is zero. This opens up new possibilities for the experimental observation of this…
We demonstrate the fundamental links existing between two different descriptions of quantum electrodynamics in inhomogeneous, lossy and dispersive dielectric media which are based either on the Huttner-Barnett formalism for polaritons [B. Huttner and S. M. Barnett, Phys.Rev. A 46, 4306 (1992)] or the Langevin noise approach using fluctuating currents [T. Gruner and D.-G. Welsch, Phys.Rev.A 53, 1818 (1996)]. In this work we demonstrate the practical equivalence of the two descriptions by introducing the concept of effective photon state associated with some specific noise current distribution. …
Nonclassical microwave radiation from the parametric dynamical Casimir effect in the reversed-dissipation regime of circuit optomechanics
University of Isfahan（伊斯法罕大学）；Center of Quantum Science and Technology, University of Isfahan（伊斯法罕大学量子科学与技术中心）；Department of Physics, College of Science, University of Tehran（德黑兰大学理学院物理系）；Quantum Remote Sensing Lab, Quantum Metrology Group, Iranian Center for Quantum Technologies（伊朗量子技术中心量子计量组量子遥感实验室）；Quantum Optics Group, Department of Physics, University of Isfahan（伊斯法罕大学物理系量子光学小组）；Laboratory of Photonics and Quantum Measurement, Swiss Federal Institute of Technology Lausanne（洛桑联邦理工学院光子学与量子测量实验室）；EDWATEC SA
We investigate the dispersive Casimir-Polder interaction between a Rubidium atom and a suspended graphene sheet subjected to an external magnetic field B. We demonstrate that this concrete physical system allows for an unprecedented control of dispersive interactions at micro and nanoscales. Indeed, we show that the application of an external magnetic field can induce a 80% reduction of the Casimir-Polder energy relative to its value without the field. We also show that sharp discontinuities emerge in the Casimir-Polder interaction energy for certain values of the applied magnetic field at low…
