Physical Review A (24699934)110(1)
Entanglement formation between the magnons as the internal degrees of freedom and the center-of-mass motion (CM) as the external degrees of freedom of a levitated yttrium iron garnet (YIG) sphere in a cavity-magnomechanical system is studied. Here, we propose a scheme for generating magnon-CM entanglement independent from the mass and size of the sphere in the hybrid magnonic system by driving the magnon with the parametric amplification. First, we show that the power and frequency of the driving field significantly affect this entanglement, since the driving field increases effective magnon-CM coupling. But, by increasing the magnon damping rate, this entanglement considerably decreases. Moreover, in the next step, we demonstrate the manipulation and enhancement of this entanglement by driving the magnon into the squeezed state. Our results present an approach for preparing quantum states and may find promising applications in the quantum metrology and sensing. © 2024 American Physical Society.
Physical Review A (24699934)109(5)
Accurate temperature measurement is critical in many scientific and engineering fields, so that researchers continuously strive to improve the accuracy, sensitivity, and robustness of the current measurement methods. In this paper, we propose a theoretical approach for temperature measurement using an optomechanical system in which the position of a mechanical oscillator is coupled to the cavity field. Our approach enables precise control and manipulation of both, resulting in highly accurate temperature measurements. We evaluate the accuracy of temperature estimation by using classical and quantum Fisher information, considering both open and closed systems, and investigate entanglement effects of the primary field mode. Our findings indicate that increasing entanglement at the input made reduces measurement time and increases sensitivity in estimating the temperature. However, we observe that quantum coherence is destroyed by decoherence, leading to reduced performance of quantum systems. Furthermore, we show that the Fisher information of the system is robust against mechanical decoherence, but significantly damped due to optical decoherence. We discuss the limitations and challenges of our method and suggest possible applications and future directions for our research. Finally, we determine the accuracy of temperature estimation for a typical optomechanical system based on phase values measured in the closed system. Our results demonstrate the potential of optomechanical systems for highly accurate temperature measurement and their robustness against decoherence. This study can provide insights into the field of temperature measurement, offering a theoretical approach that can be applied in many scientific and engineering applications. © 2024 American Physical Society.
Optics Express (10944087)32(9)pp. 14914-14928
In this paper, we theoretically investigate the magnomechanically induced transparency (MIT) phenomenon and slow-fast light propagation in a microwave cavity-magnomechanical system which includes a levitated ferromagnetic sphere. Magnetic dipole interaction determines the interaction between the photon, magnon, and center of mass motion of the cavity-magnomechanical system. As a result, we find that apart from coupling strength, which has an important role in MIT, the levitated ferromagnetic sphere’s position provides us a parameter to manipulate the width of the transparency window. In addition, the control field’s frequency has crucial influences on the MIT. Also this hybrid magnonic system allows us to demonstrate MIT in both the strong coupling and intermediate coupling regimes. More interestingly, we demonstrate tunable slow and fast light in this hybrid magnonic system. In other words, we show that the group delay can be adjusted by varying the control field’s frequency, the sphere position, and the magnon-photon coupling strength. These parameters have an influence on the transformation from slow to fast light propagation and vice versa. Based on the recent experimental advancements, our results provide the possibility to engineer hybrid magnonic systems with levitated particles for the light propagation, and the quantum measurements and sensing of physical quantities. © 2024 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.
International Journal of Geometric Methods in Modern Physics (17936977)19(9)
In this paper, the Higgs-like approach is used to analyze the quantum dynamics of a harmonic oscillator constrained on a circle. We obtain the Hamiltonian of this system as a function of the Cartesian coordinate of the tangent line through the gnomonic projection and then quantize it in the standard way. We then recast the Hamiltonian in a shape-invariant form and derive the spectrum energy of the confined harmonic oscillator on the circle. With help of the f-deformed oscillator algebra, we construct the coherent states on the circle and investigate their quantum statistical properties. We find that such states show nonclassical features like squeezing and sub-Poissonian statistics even in small curvatures of the circle. © 2022 World Scientific Publishing Company.
Journal of the Optical Society of America B: Optical Physics (07403224)39(5)pp. 1353-1363
In this paper, to study the effects of a nonlinear medium on the atom-field interaction, we use the nonlinear coherent states approach. For this purpose, we choose the two-mode cross-Kerr as our nonlinear optical phenomena, and with the use of its algebra, we show that it can be considered as a deformed oscillator as well as a deformed su(2) algebra. Then we construct the associated two-mode nonlinear coherent states and investigate their statistical properties. After that, as an example of applicability of the constructed coherent states, we investigate the nonlinear effects of the medium on the dynamics of atom-field interaction within the framework of the coherent states. By using the time-dependent Schrödinger equation, we study the effect of the nonlinear medium on the occupation probabilities of the atomic levels and consider the relation between the revival time of the atomic occupation probabilities and the nonlinear parameter of the medium. Then, to study the nonlinear effects on the dynamical properties of the cavity field, we consider the photon distribution, correlation function, Mandel parameters of the field, von Neumann entropy, and also the squeezing. Particularly, the nonlinearity of the media on the nonclassical properties of the two modes is clarified. © 2022 Optica Publishing Group
Physics Letters, Section A: General, Atomic and Solid State Physics (03759601)384(26)
In this paper, we introduce an algebraic approach to construct Fokas-Lagerstrom coherent states. To do so, we define deformed creation and annihilation operators associated to this system and investigate their algebra. We show that these operators satisfy the f-deformed Weyl-Heisenberg algebra. Then, we propose a theoretical scheme to generate the aforementioned coherent states. The present contribution shows that the Fokas-Lagerstrom nonlinear coherent states possess some non-classical features. © 2020
Hoseinzadeh, M.,
Amooghorban, E.,
Mahdifar, A.,
Nafchi, M.A. Physical Review A (24699934)101(4)
In this paper, we present a phenomenological quantization of the electromagnetic field in the presence of a moving absorptive and dispersive magnetodielectric slab (MDS) with uniform velocity in the direction parallel to its interface. As our main result, we use this quantization scheme to derive the quantum input-output relations for the case in which quantum states propagate perpendicularly to the moving MDS. We thoroughly investigate the impact of the motion of the moving MDS on quantum properties of the incident states. To illustrate this, we compute the quadrature squeezing and the Mandel parameter for the transmitted state when the incident states from left and right sides are, respectively, the coherent and the quantum vacuum states. We find that the quantum features of the incident state are degraded through transmission in the moving MDS in the low- and moderate-velocity ranges. © 2020 American Physical Society.
Dehdashti, S.,
Yasar f., ,
Harouni, M.B.,
Mahdifar, A.,
Mirza, B. Quantum Information Processing (15700755)19(9)
In this paper, we study the spin-bosonic model, with and without tunneling terms, in detail. The spin-bosonic model without tunneling is studied by using the thermofield dynamics approach. Indeed, by considering temperature, we show that environmental states, while they become entangled with system, approach thermal coherent states with different phases. In addition, by considering the tunneling term, we study the interplay of the environmental cut-off frequency as well as the impacts of environmental temperature on the quantum speed limit in both cases, i.e., spin-boson system with and without tunneling term. In these studies, we indicate temperature play more important role in compare with cut-off frequency to control the quantumness of a spin system. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.
Iranian Journal of Physics Research (16826957)20(2)pp. 195-205
In this paper, by using the quantum input-output relations for an anisotropic slab, we investigate the quadrature squeezing and Mandel parameters of the transmitted squeezed coherent state through a metamaterial slab with negative refractive index and also a hyperbolic metamaterial slab. It will be shown that the nonclassical properties of the aforementioned state decrease sharply in passing through the negative refractive index slab. While, the hyperbolic metamaterial slab with a small absorption coefficient can somewhat retain the nonclassical properties of the incident squeezed light. © 2020, Isfahan University of Technology. All rights reserved.
Journal of Mathematical Physics (10897658)60(8)
In this paper, we investigate the dynamics of both a free particle and an isotropic harmonic oscillator constrained to move on a spheroidal surface using two consecutive projections: a projection onto a sphere surface followed by the gnomonic projection onto a tangent plane to the spheroid. We obtain the Hamiltonian of the aforementioned systems in terms of the Cartesian coordinates of the tangent plane and then quantize it in the standard way. It is shown that the effect of nonsphericity of the surface can be treated as the appearance of an effective potential. By using the perturbation theory up to the first order in the second eccentricity of the spheroid, we approximately calculate the eigenfunctions and eigenvalues of the free particle as well as the isotropic harmonic oscillator on the spheroidal surface. We find that the deviation from the sphericity plays an important role in splitting the energy levels of the isotropic oscillator on a sphere and lifting the degeneracy. © 2019 Author(s).
Iranian Journal of Physics Research (16826957)19(2)pp. 379-390
In this paper, we construct the Gazeau-Klauder coherent states of a two- dimensional harmonic oscillator on a sphere based on two equivalent approaches. First, we consider the oscillator on the sphere as a deformed (non-degenerate) one-dimensional oscillator. Second, the oscillator on the sphere is considered as the usual (degenerate) two--dimensional oscillator. Then, by investigating the quantum optical properties of the constructed coherent states, we study the effect of the space curvature on the properties of the constructed sphere Gazeau-Klauder coherent states, according to these two approaches. © 2019, Isfahan University of Technology. All rights reserved.
Journal of Mathematical Physics (10897658)59(7)
In this paper, we construct the m-photon-added and m-photon-subtracted coherent states on a sphere. These states are shown to satisfy the usual conditions of continuity in the label, normalizability, and the resolution of identity. The preparation of the constructed states, as the states of the radiation field, is considered. We examine and analyze the nonclassical properties of these states, including the photon mean number, Mandel parameter, and quadrature squeezing. We find that these states are sub-Poissonian in nature, whereas the degree of squeezing is reduced (enhanced) by increasing m for the photon-added (photon-subtracted) coherent states on a sphere. The results also exhibit that the curvature of the sphere contributes to the enhancement of nonclassical behavior of the photon-added and photon-subtracted coherent states on the sphere. © 2018 Author(s).
Iranian Journal of Physics Research (16826957)18(2)pp. 263-280
In this paper, we consider a system including two maghnetodielectric slabs with different temperature that are placed in vacuum at zero temperature and very short separation distances from each other. Based on the canonical quantization of the electromagnetic field in the presence of dissipative media, we investigate the radiative heat transfer arising from thermal and quantum fluctuations in out of thermal equilibrium but stationary situation. For this purpose, we calculate the ensemble average of Poynting vector by driving quantum correlation relations between noise polarization and magnetization operators and extracting the electromagnetic Green tensor of the system. Finally, we analyze the transferred radiation of aforementioned system by employing the numerical result of the Poynting vector. © 2018, Isfahan University of Technology. All rights reserved.
Optics Communications (00304018)426pp. 63-69
In this paper, based on a canonical quantization scheme, we study the effect of the relativistic motion of an excited atom on its decay rate in the presence of absorbing and dispersive media. For this purpose, we introduce an appropriate Lagrangian and describe the center-of-mass dynamical variables by the Dirac field. We obtain the Hamiltonian of the system in a multipolar form and calculate the motion equations of the system in the Schrödinger picture. We find that the decay rate and the quantum electrodynamics level shift of the moving atom can be expressed in terms of the imaginary part of the classical Green tensor and the center-of-mass velocity of the atom. © 2018 Elsevier B.V.
Iranian Journal of Physics Research (16826957)17(1)pp. 21-32
In this paper, with respect to the advantages of geometric phase in quantum computation, we calculate the geometric phase of the optomechanical systems. This research can be considered as an important step toward using the optomechanical systems in quantum computation with utilizing its geometric phase. © 2017, Isfahan University of Technology. All rights reserved.
Iranian Journal of Physics Research (16826957)16(4)pp. 305-318
In this paper, we quantize electromagnetic field in, lossy, dispersive and anisotropic magnetodielectric media by using phenomenological approach. We obtain quantum input– output relations for anisotropic multilayer metamaterials. As an application of our approach, we investigate the dissipative and anisotropic effects of an anisotropic magnetodielectric slab on the quantum properties of incident input states. For this purpose, quadrature squeezing and Mandel parameter of output states has been calculated by modeling the anisotropic magnetodielectric slab through Lorentz model for a situation in which the incident states on the right and left side of the magnetodielectric slab are two- mode coherent states and quantum vacuum state, respectively. © 2017, Isfahan University of Technology. All rights reserved.
European Physical Journal D (14346060)71(11)
Abstract: In this paper, we examine the modification of specific nonclassical properties of the sphere coherent state upon perpendicular propagation through an absorptive and dispersive dielectric slab at finite temperature. To achieve this purpose, by describing the dielectric dispersion of the slab by Lorentz model, the quadrature squeezing and the Mandel parameter are evaluated for the transmitted state. A generalization of the single-mode sphere coherent state to a continuum-mode is considered. The degree of second-order coherence is calculated for a continuum sphere coherent state, and the quantum noise effects produced by transmission through the slab on the antibunching feature are examined. We find that near the medium resonance the detrimental effect of the loss and thermal fluctuations of the slab are not compensated with increasing the physical space curvature of the incident state. Graphical abstract: [Figure not available: see fulltext.]. © 2017, EDP Sciences, SIF, Springer-Verlag GmbH Germany, part of Springer Nature.
International Journal of Theoretical Physics (15729575)55(8)pp. 3564-3578
In this paper, we study Gazeau-Klauder and displacement-type coherent states of two-dimensional position-dependent mass oscillators, which is called Λ-dependent oscillators and Λ can be interpreted as the curvatures of the spherical and the hyperbolic spaces, on which oscillators are constrained. In addition, we consider the effect of Λ parameter on the physical properties of these coherent states, including minimized Heisenberg uncertainty relation and Mandel’s Q parameter. We also elaborate the relation between the curvature of the physical space and the curvature of the Λ-dependent coherent state manifold. © 2016, Springer Science+Business Media New York.
International Journal of Theoretical Physics (15729575)55(1)pp. 124-136
In this paper, we study the quantum free particle on the spherical space by applying da costa approach for quantum particle on the curved space. We obtain the discrete energy eigenvalues and associated normalized eigenfunctions of the free particle on the sphere. In addition, we introduce the Gazeau-Klauder coherent states of free particle on the sphere. Then, the Gaussian coherent states is defined, which is used to describe the localized particle on the spherical space. Finally, we study the relation between the f-deformed coherent states and Gazeau-Klauder ones for this system. © 2015, Springer Science+Business Media New York.
Physical Review A (24699934)94(1)
As a probe to explore the ability of invisibility cloaks to conceal objects in the quantum mechanics domain, we study the spontaneous emission rate of an excited two-level atom in the vicinity of an ideal invisibility cloaking. On this base, first, a canonical quantization scheme is presented for the electromagnetic field interacting with atomic systems in an anisotropic, inhomogeneous, and absorbing magnetodielectric medium which can suitably be used for studying the influence of arbitrary invisibility cloak on the atomic radiative properties. The time dependence of the atomic subsystem is obtained in the Schrodinger picture. By introducing a modified set of the spherical wave-vector functions, the Green tensor of the system is calculated via exact and discrete methods. In this formalism, the decay rate and as well the emission pattern of the aforementioned atom are computed analytically for both weak and strong coupling interaction, and then numerically calculations are done to demonstrate the performances of cloaking in the quantum mechanics domain. Special attention is paid to different possible orientations and locations of the atomic system near the spherical invisibility cloaking. Results in the presence and the absence of the invisibility cloak are compared. We find that the cloak works very well far from its resonance frequency to conceal a macroscopic object, whereas at near the resonance frequency the object is more visible than the situation where the object is not covered by the cloak. © 2016 American Physical Society.
Annals of Physics (00034916)355pp. 21-34
An algebraic approach to Kepler problem in a curved space is introduced. By using this approach, the creation and annihilation operators associated to this system and their algebra are calculated. These operators satisfy a deformed Weyl-Heisenberg algebra which can be assumed as a deformed su(2) algebra. By using this fact, the nonlinear coherent states of this system are constructed. The scalar product and Bargmann representation of this family of nonlinear coherent states are constructed. The present contribution shows that these nonlinear coherent states possess some non-classical features which strongly depend on the Kepler coupling constant and space curvature. Depending on the non-classical measures, the smaller the curvature parameter, the more the non-classical features. Moreover, the stronger Kepler constant provides more non-classical features. © 2015 Elsevier Inc.
Quantum Information Processing (15700755)14(8)pp. 2895-2907
In this paper, we investigate the behavior of radiation field, whose state is described by the so-called sphere coherent state, through a beam splitter. These states are realization of coherent states of two-dimensional harmonic oscillator, which lives on a sphere, as radiation field. By using the linear entropy as a measure of entanglement, we show that the entanglement depends on the curvature of the sphere. So, by using the appropriating sphere coherent states, we can control the entanglement of the output states of the beam splitter in the laboratory. In addition, as the convince measures of non-classical behaviors, we consider Mandel parameters of the output states of the beam splitter and their quadrature squeezing. © 2015, Springer Science+Business Media New York.
Annals of Physics (00034916)360pp. 237-245
By using a continuum of oscillators as a reservoir, we present a classical and a quantum-mechanical treatment for the Higgs model in the presence of dissipation. In this base, a fully canonical approach is used to quantize the damped particle on a spherical surface under the action of a conservative central force, the conjugate momentum is defined and the Hamiltonian is derived. The equations of motion for the canonical variables and in turn the Langevin equation are obtained. It is shown that the dynamics of the dissipative Higgs model is not only determined by a projected susceptibility tensor that obeys the Kramers-Kronig relations and a noise operator but also the curvature of the spherical space. Due to the gnomonic projection from the spherical space to the tangent plane, the projected susceptibility displays anisotropic character in the tangent plane. To illuminate the effect of dissipation on the Higgs model, the transition rate between energy levels of the particle on the sphere is calculated. It is seen that appreciable probabilities for transition are possible only if the transition and reservoir's oscillators frequencies to be nearly on resonance. © 2015 Elsevier Inc.
Laser Physics (1054660X)24(5)
We study the dynamics of a catlike superposition of f-deformed coherent states under dissipative decoherence. For this purpose, we investigate two important categories of f-deformed coherent states: Gazeau-Klauder and displacement-type coherent states. In addition, we consider two deformation functions; one of them describes a harmonic oscillator in an infinite well and another corresponds to a harmonic oscillator in a quantum well with finite depth. The decoherence effects appeared through a dissipative interaction of the environment with the catlike states. In this study, we first show that the Gazeau-Klauder coherent state is more resistant under the decoherence process, in contrast to the displacement-type one, and second, that the potential range of the infinite well and the depth of potential possess a remarkable role in the decoherence process. © 2014 Astro Ltd.
Modern Physics Letters A (02177323)29(19)
We study the two-dimensional harmonic oscillator on a noncommutative plane. We show that by introducing appropriate Bopp shifts, one can obtain the Hamiltonian of a two-dimensional harmonic oscillator on a sphere according to the Higgs model. By calculating the commutation relations, we show that this noncommutativity is strictly dependent on the curvature of the background space. In other words, we introduce a kind of duality between noncommutativity and curvature by introducing noncommutativity parameters as functions of curvature. Also, it is shown that the physical realization of such model is a charged harmonic oscillator in the presence of electromagnetic field. © 2014 World Scientific Publishing Company.
Iranian Journal of Physics Research (16826957)13(4)pp. 347-354
In this paper, in order to study a nonlinear dissipative cavity a linear master equation of the cavity in generalized to a nonlinear one at zero temperature. Then, it is shown that nonlinear coherent states are the only preferred states of the system under decoherence.
Journal of Modern Optics (13623044)60(3)pp. 233-239
In this paper, to obtain an analogy between the curved spaces and the linear optics, we expand the idea of Sánchez-Soto and co-workers [Phys. Rep. 2012, 513, 191; Phys. Rev. A 2011, 84, 023830] to the multilayer films. We investigate effects of thickness and index of refraction of the films on the Lorentzian transformations. In addition, by using the multilayer films, we suggest a very simple experimental set-up which can serve as an analogue computer for testing special relativity. Finally, we draw an analogy between the Rindler space, as an example of the curved spaces, and a suitable multilayer film. Copyright © 2013 Taylor & Francis.
International Journal of Geometric Methods in Modern Physics (17936977)10(5)
At first, we introduce -deformed algebra as a kind of generalization of the Weyl-Heisenberg algebra so that we get the su(2)-and su(1, 1)-algebras whenever has specific values. After that, we construct coherent states of this algebra. Third, a realization of this algebra is given in the system of a harmonic oscillator confined at the center of a potential well. Then, we introduce two-boson realization of the -deformed Weyl-Heisenberg algebra and use this representation to write -deformed coherent states in terms of the two modes number states. Following these points, we consider mean number of excitations (we call them in general photons) and Mandel parameter as statistical properties of the -deformed coherent states. Finally, the Fubini-Study metric is calculated for the -coherent states manifold. © 2013 World Scientific Publishing Company.
International Journal of Geometric Methods in Modern Physics (17936977)10(7)
In this paper, we generalize Schwinger realization of the su(2) algebra to construct a two-mode realization for deformed su(2) algebra on a sphere. We obtain a nonlinear (f-deformed) Schwinger realization with a deformation function corresponding to the curvature of sphere that in the flat limit tends to unity. With the use of this nonlinear two-mode algebra, we construct the associated two-mode coherent states (CSs) on the sphere and investigate their quantum entanglement. We also compare the quantum statistical properties of the two modes of the constructed CSs, including anticorrelation and antibunching effects. Particularly, the influence of the curvature of the physical space on the nonclassical properties of two modes is clarified. © 2013 World Scientific Publishing Company.
Journal of the Optical Society of America B: Optical Physics (07403224)30(11)pp. 2952-2959
In this paper, we consider the interaction of the nonlinear coherent states (CSs) on a sphere with a three-level atom. Since these generalized CSs depend on the curvature of the sphere, this model enables us to investigate the curvature effects of the physical space. By using the time-dependent state of the atom-field system, we first study the curvature effects on the occupation probabilities of the atomic levels. We especially study the relation between the revival time of the atomic occupation probabilities and the curvature. Then, to study the curvature effects on the dynamical properties of the cavity field, we consider photon distributions, correlation functions, and Mandel parameters of the field. The cavity field in this atom-field system exhibits nonclassical features which depend on the curvature of the physical space. © 2013 Optical Society of America.
Annals of Physics (00034916)334pp. 321-333
The decoherence rate and some parameters affecting it are investigated for the generalized spin-boson model. We consider the spin-bosonic model when the bosonic environment is modeled by the deformed harmonic oscillators. We show that the state of the environment approaches a non-linear coherent state. Then, we obtain the decoherence rate of a two-level system which is in contact with a deformed bosonic environment which is either in thermal equilibrium or in the ground state. By using some recent realization of f-deformed oscillators, we show that some physical parameters strongly affect the decoherence rate of a two-level system. © 2013 Elsevier Inc.
Iranian Journal of Physics Research (16826957)13(1)pp. 65-75
In this paper, by using the nonlinear coherent states on a sphere, we introduce superposition of the aforementioned coherent states. Then, we consider quantum optical properties of these new superposed states and compare these properties with the corresponding properties of the nonlinear coherent states on the sphere. Specifically, we investigate their characteristics function, photon-number distribution, Mandel parameter, quadrature squeezing, anti-bunching effect and Wigner function, and obtain the curvature effect on the properties of the superposed states. Finally, by using the trapped atom system, we introduce a theoretical scheme to generate superposition of the coherent states on the sphere.
Journal of Mathematical Physics (10897658)54(5)
In this paper, we first define thermal nonlinear coherent states on a sphere and show that these states are essentially two-mode squeezed nonlinear coherent states of the sphere at zero temperature. Then we consider quantum statistical properties of the thermal sphere nonlinear coherent states. In particular, we investigate temperature effects on transition of the constructed states from nonclassical states to classical ones. By using the Mandel parameter, we obtain a transition temperature and show that this transition temperature increases by increasing the curvature of the physical space. It turns out that, increasing curvature of the space provides nonlinear coherent states with nonclassical properties in higher temperature ranges. © 2013 AIP Publishing LLC.
International Journal of Geometric Methods in Modern Physics (17936977)9(1)
In this paper, by using the nonlinear coherent states approach, we find a relation between the geometric structure of the physical space and the geometry of the corresponding projective Hilbert space. To illustrate the approach, we explore the quantum transition probability and the geometric phase in the curved space. © 2012 World Scientific Publishing Company.
Journal of Physics A: Mathematical and Theoretical (17518113)45(46)
In this paper, we investigate a two-dimensional isotropic harmonic oscillator on a time-dependent spherical background. The effect of the background can be represented as a minimally coupled field to the oscillator's Hamiltonian. For a fluctuating background, transition probabilities per unit time are obtained. Transitions are possible if the energy eigenvalues of the oscillator E i and frequencies of the fluctuating background ω n satisfy the following two simple relations: E j≃E i ω n (stimulated emission) and E j≃E i + h d ω n (absorption). This indicates that a background fluctuating at a frequency of ω n interacts with the oscillator as a quantum field of the same frequency. We believe this result is also applicable for an arbitrary quantum system defined on a fluctuating maximally symmetric background. © 2012 IOP Publishing Ltd.
Physical Review A - Atomic, Molecular, and Optical Physics (10502947)78(6)
The preparation of coherent states of the harmonic oscillator on a sphere is considered. Based on the nonlinear coherent states of the atomic center-of-mass motion of a trapped ion, one may control the laser-ion interaction in such a way that sphere coherent states are obtained as motional dark states of the system. The curvature can be controlled by the Rabi frequencies of the driving lasers. The nonclassical properties of the resulting quantum states are analyzed. By variation of the curvature of the sphere, the states can be tuned continuously between spin-squeezed states and motional Fock states. © 2008 The American Physical Society.
AIP Conference Proceedings (0094243X)956pp. 245-250
In this paper, we investigate the relation between the curvature of the physical space and the deformation function of the deformed oscillator algebra using a non-linear coherent states approach. © 2007 American Institute of Physics.
Journal of Physics A: Mathematical and General (13616447)39(22)pp. 7003-7014
In this paper, we investigate the relation between the curvature of the physical space and the deformation function of the deformed oscillator algebra using the nonlinear coherent states approach. For this purpose, we study two-dimensional harmonic oscillators on the flat surface and on a sphere by applying the Higgs model. With the use of their algebras, we show that the two-dimensional oscillator algebra on a surface can be considered as a deformed one-dimensional oscillator algebra where the effect of the curvature of the surface appears as a deformation function. We also show that the curvature of the physical space plays the role of deformation parameter. Then we construct the associated coherent states on the flat surface and on a sphere and compare their quantum statistical properties, including quadrature squeezing and antibunching effect. © 2006 IOP Publishing Ltd.
