Nonlinear displaced Kerr state and its nonclassical properties
01 Jul 2016-Journal of The Optical Society of America B-optical Physics (Optical Society of America)-Vol. 33, Iss: 7, pp 1511-1522
TL;DR: In this article, a distinct class of nonlinear displaced Kerr states by application of the displacement operator upon a state which is prepared by sending the well-known photon-added coherent state through a normal Kerr medium was constructed.
Abstract: We construct a distinct class of nonlinear displaced Kerr states by application of the displacement operator upon a state which is prepared by sending the well-known photon-added coherent state through a normal Kerr medium. A sketch for the experimental setup for preparing the state is suggested. We evaluate some statistical properties such as the photon number distribution, Mandel’s Q parameter, Husimi-Q and Wigner functions, and quadrature squeezing for the nonlinear displaced Kerr state and then analyze the nonclassicality in terms of these standard parameters. We reduce the infinite-level problem to a truncated discrete two-level system by using a low Kerr parameter approximation and then convert the generated nonclassicality into bipartite entanglement between the two modes of an output state of a linear optical device.
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01 Jul 2012
TL;DR: In this paper, the effect of local photon additions and subtractions on a two-mode squeezed vacuum state was investigated, and it was shown that the entanglement generally increases with the number of such operations.
Abstract: The non-Gaussian operations effected by adding or subtracting a photon on entangled optical beams emerging from a parametric down-conversion process have been suggested to enhance entanglement. Heralded photon addition or subtraction is, as a matter of fact, at the heart of continuous-variable entanglement distillation. The use of such processes has recently been experimentally demonstrated in the context of the generation of optical coherent-state superpositions or the verification of canonical commutation relations. Here, we carry out a systematic study of the effect of local photon additions and subtractions on a two-mode squeezed vacuum state, showing that the entanglement generally increases with the number of such operations. This is analytically proven when additions or subtractions are restricted to one mode only, while we observe that the highest entanglement is achieved when these operations are equally shared between the two modes. We also note that adding photons typically provides a stronger entanglement enhancement than subtracting photons, while photon subtraction performs better in terms of energy efficiency. Furthermore, we analyze the interplay between entanglement and non-Gaussianity, showing that it is more subtle than previously expected.
14 citations
TL;DR: In this paper, the nonlinear coherent states with negative m corresponding to the nonharmonic oscillators are constructed and some nonclassical properties associated with these states such as the Mandel parameter, quadrature squeezing and second-order correlation function are investigated.
Abstract: In this paper, based on the nonlinear coherent states formalism and using the Hamiltonian for a single mode field in a Kerr medium, the deformed photon-added nonlinear coherent states with negative m corresponding to the nonharmonic oscillators are constructed. In addition, some of the nonclassical properties associated with these states such as the Mandel parameter, quadrature squeezing and second-order correlation function are investigated. It is found that the deformed photon-added nonlinear coherent states with negative m for the one-mode field in a Kerr medium are nonclassical states.
5 citations
23 Jan 2023
TL;DR: In this article , a general computational framework for optimizing model-dependent parameters in quantum batteries is proposed and applied to two different charging scenarios in the micromaser QB and a new charging protocol for stabilizing the battery in upper-laying Hilbert space chambers in a controlled and automatic way.
Abstract: We propose a general computational framework for optimizing model-dependent parameters in quantum batteries (QB). We apply this method to two different charging scenarios in the micromaser QB and we discover a new charging protocol for stabilizing the battery in upper-laying Hilbert space chambers in a controlled and automatic way. This protocol is found to be stable and robust, and it leads to an improved charging efficiency in micromaser QBs. Moreover, our optimization framework is highly versatile and efficient, holding great promise for the advancement of QB technologies at all scales.
3 citations
TL;DR: In this paper, the authors describe a superposition of field annihilation and creation operators acting on a continuous variable coherent state and analyze the lower and higher-order nonclassical properties of |ψ⟩.
Abstract: A coherent state is defined conventionally in different ways such as
a displaced vacuum state, an eigenket of an annihilation operator, or as
an infinite dimensional Poissonian superposition of Fock states. In this
work, we describe a superposition
(ta+ra†) of field annihilation and
creation operators acting on a continuous variable coherent state
|α⟩ and specify it by |ψ⟩. We analyze the lower- as well as
higher-order nonclassical properties of |ψ⟩. The comparison is
performed by using a set of nonclassicality witnesses (e.g., higher-order
photon statistics, higher-order antibunching, higher-order sub-Poissonian
statistics, higher-order squeezing, Agarwal–Tara parameter, Klyshko’s
condition, and a relatively new concept, matrix of phase-space
distribution). It is found that the higher-order criteria are much more
efficient to detect the presence of nonclassicality as compared to
lower-order conditions except squeezing, where the lower-order one is more
competent than its higher-order counterpart.
2 citations
Journal Article•
TL;DR: In this paper, nonlinear photon-added displaced Kerr states are introduced as the output field of a Mach-Zehnder interferometer including the Kerr medium when the input fields are the deformed photon-add coherent state and the vacuum state.
Abstract: In this paper, nonlinear photon-added displaced Kerr states are introduced as the output field of a Mach-Zehnder interferometer including the Kerr medium when the input fields are the deformed photon-added coherent state and the vacuum state. As the physical realization, the presented approach is applied to the Poschl-Teller potential and their photon number distribution and Mandel parameter are studied. The results show that the introduced states can be considered as the nonclassical states.
References
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