The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Jungtsung Shen - One of the best experts on this subject based on the ideXlab platform.

Shanhui Fan - One of the best experts on this subject based on the ideXlab platform.

Valerio Scarani - One of the best experts on this subject based on the ideXlab platform.

  • solving the scattering of n photons on a two Level Atom without computation
    New Journal of Physics, 2016
    Co-Authors: Alexandre Roulet, Valerio Scarani
    Abstract:

    We propose a novel approach for solving the scattering of light onto a two-Level Atom coupled to a one-dimensional waveguide. We first express the physical quantity of interest in terms of Feynman diagrams and treat the Atom as a non-saturable linear beamsplitter. By using the Atomic response to our advantage, a relevant substitution is then made that captures the nonlinearity of the Atom, and the final result is obtained in terms of simple integrals over the initial incoming wavepackets. The procedure is not limited to post-scattering quantities and allows for instance to derive the Atomic excitation during the scattering event.

  • efficient excitation of a two Level Atom by a single photon in a propagating mode
    Physical Review A, 2011
    Co-Authors: Yimin Wang, Jiři Minař, Lana Sheridan, Valerio Scarani
    Abstract:

    State mapping between Atoms and photons, and photon-photon interactions play an important role in scalable quantum information processing. We consider the interaction of a two-Level Atom with a quantized propagating pulse in free space and study the probability P{sub e}(t) of finding the Atom in the excited state at any time t. This probability is expected to depend on (i) the quantum state of the pulse field and (ii) the overlap between the pulse and the dipole pattern of the Atomic spontaneous emission. We show that the second effect is captured by a single parameter {Lambda}(set-membership sign)[0,8{pi}/3], obtained by weighting the dipole pattern with the numerical aperture. Then, P{sub e}(t) can be obtained by solving time-dependent Heisenberg-Langevin equations. We provide detailed solutions for both single-photon Fock state and coherent states and for various temporal shapes of the pulses.

  • efficient excitation of a two Level Atom by a single photon in a propagating mode
    Physical Review A, 2011
    Co-Authors: Yimin Wang, Jiři Minař, Lana Sheridan, Valerio Scarani
    Abstract:

    State mapping between Atoms and photons, and photon-photon interactions play an important role in scalable quantum information processing. We consider the interaction of a two-Level Atom with a quantized propagating pulse in free space and study the probability ${P}_{e}(t)$ of finding the Atom in the excited state at any time $t$. This probability is expected to depend on (i) the quantum state of the pulse field and (ii) the overlap between the pulse and the dipole pattern of the Atomic spontaneous emission. We show that the second effect is captured by a single parameter $\ensuremath{\Lambda}\ensuremath{\in}[0,8\ensuremath{\pi}/3]$, obtained by weighting the dipole pattern with the numerical aperture. Then, ${P}_{e}(t)$ can be obtained by solving time-dependent Heisenberg-Langevin equations. We provide detailed solutions for both single-photon Fock state and coherent states and for various temporal shapes of the pulses.

Eden Rephaeli - One of the best experts on this subject based on the ideXlab platform.

Mohammad Javad Faghihi - One of the best experts on this subject based on the ideXlab platform.

  • dynamics of entanglement of a three Level Atom in motion interacting with two coupled modes including parametric down conversion
    Physica A-statistical Mechanics and Its Applications, 2014
    Co-Authors: Mohammad Javad Faghihi, M K Tavassoly, Mohsen Hatami
    Abstract:

    Abstract In this paper, a model by which we study the interaction between a motional three-Level Atom and two-mode field injected simultaneously in a bichromatic cavity is considered; the three-Level Atom is assumed to be in a Λ -type configuration. As a result, the Atom–field and the field–field interaction (parametric down conversion) will be appeared. It is shown that, by applying a canonical transformation, the introduced model can be reduced to a well-known form of the generalized Jaynes–Cummings model. Under particular initial conditions, which may be prepared for the Atom and the field, the time evolution of state vector of the entire system is analytically evaluated. Then, the dynamics of Atom by considering ‘Atomic population inversion’ and two different measures of entanglement, i.e., ‘von Neumann entropy’ and ‘idempotency defect’ is discussed, in detail. It is deduced from the numerical results that, the duration and the maximum amount of the considered physical quantities can be suitably tuned by selecting the proper field-mode structure parameter p and the detuning parameters.

  • tripartite entanglement dynamics and entropic squeezing of a three Level Atom interacting with a bimodal cavity field
    arXiv: Quantum Physics, 2014
    Co-Authors: Mohammad Javad Faghihi, M K Tavassoly, Bagheri M Harouni
    Abstract:

    In this paper, we study the interaction between a $\Lambda$-type three-Level Atom and two quantized electromagnetic fields which are simultaneously injected in a bichromatic cavity surrounded by a Kerr medium in the presence of the field-field interaction (parametric down conversion) and detuning parameters. By applying a canonical transformation, the introduced model is reduced to a well-known form of the generalized Jaynes-Cummings model. Under particular initial conditions which may be prepared for the Atom and the field, the time evolution of state vector of the entire system is analytically evaluated. Then, the dynamics of Atom is studied through the evolution of the Atomic population inversion. In addition, two different measures of entanglement between the tripartite system (three entities make the system: two field modes and one Atom) i.e., von Neumann and linear entropy are investigated. Also, two kinds of entropic uncertainty relations, from which entropy squeezing can be obtained, are discussed. In each case, the influences of the detuning parameters and Kerr medium on the above nonclassicality features are analyzed via numerical results, in detail. It is illustrated that the amount of the above-mentioned physical phenomena can be tuned by choosing the evolved parameters, appropriately.

  • tripartite entanglement dynamics and entropic squeezing of a three Level Atom interacting with a bimodal cavity field
    Laser Physics, 2014
    Co-Authors: Mohammad Javad Faghihi, M K Tavassoly, Bagheri M Harouni
    Abstract:

    In this paper, we study the interaction between a Λ-type three-Level Atom and two quantized electromagnetic fields which are simultaneously injected in a bichromatic cavity surrounded by a Kerr medium in the presence of field–field interaction (parametric down conversion) and detuning parameters. By applying a canonical transformation, the introduced model is reduced to a well-known form of the generalized Jaynes–Cummings model. Under particular initial conditions which may be prepared for the Atom and the field, the time evolution of the state vector of the entire system is analytically evaluated. Then, the dynamics of the Atom is studied through the evolution of the Atomic population inversion. In addition, two different measures of entanglement between the tripartite system (three entities make the system: two field modes and one Atom), i.e., von Neumann and linear entropy are investigated. Also, two kinds of entropic uncertainty relations, from which entropy squeezing can be obtained, are discussed. In each case, the influences of the detuning parameters and Kerr medium on the above nonclassicality features are analyzed in detail via numerical results. It is illustrated that the amount of the above-mentioned physical phenomena can be tuned by choosing the evolved parameters, appropriately.

  • quantum entanglement and position momentum entropic squeezing of a moving lambda type three Level Atom interacting with a single mode quantized field with intensity dependent coupling
    Journal of Physics B, 2013
    Co-Authors: Mohammad Javad Faghihi, Mohammad Kazem Tavassoly
    Abstract:

    In this paper, we study the interaction between a moving Λ-type three-Level Atom and a single-mode cavity field in the presence of intensity-dependent Atom–field coupling. After obtaining the state vector of the entire system explicitly, we study the nonclassical features of the system such as quantum entanglement, position–momentum entropic squeezing, quadrature squeezing and sub-Poissonian statistics. According to the obtained numerical results we illustrate that the squeezed period, the duration of entropy squeezing and the maximal squeezing can be controlled by choosing the appropriate nonlinearity function together with entering the Atomic motion effect by the suitable selection of the field-mode structure parameter. Also, the Atomic motion, as well as the nonlinearity function, leads to the oscillatory behaviour of the degree of entanglement between the Atom and field.

  • 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
    Journal of The Optical Society of America B-optical Physics, 2013
    Co-Authors: Mohammad Javad Faghihi, M K Tavassoly, M R Hooshmandasl
    Abstract:

    In this paper, the interaction between a Λ-type three-Level Atom and a two-mode cavity field is discussed. The detuning parameters and cross-Kerr nonlinearity are taken into account, and it is assumed that the Atom–field coupling and Kerr medium are f-deformed. Even though the system seems complicated, the analytical form of the state vector of the entire system for the considered model is exactly obtained. The time evolution of nonclassical properties, such as quantum entanglement and position–momentum entropic uncertainty relation (entropy squeezing) of the field are investigated. In each case, the influences of the detuning parameters, generalized Kerr medium, and intensity-dependent coupling on the latter nonclassicality signs are analyzed in detail.