1,073 research outputs found
Generalized coherent states for the Landau levels and their nonclassical properties
Following the lines of the recent papers [J. Phys. A: Math. Theor. 44, 495201
(2012); Eur. Phys. J. D 67, 179 (2013)], we construct here a new class of
generalized coherent states related to the Landau levels, which can be used as
the finite Fock subspaces for the representation of the Lie algebra. We
establish the relationship between them and the deformed truncated coherent
states. We have, also, shown that they satisfy the resolution of the identity
property through a positive definite measures on the complex plane. Their
nonclassical and quantum statistical properties such as quadrature squeezing,
higher order `' squeezing, anti-bunching and anti-correlation effects
are studied in details. Particularly, the influence of the generalization on
the nonclassical properties of two modes is clarified.Comment: arXiv admin note: text overlap with arXiv:1212.6888, arXiv:1404.327
Generalized coherent states for pseudo harmonic oscillator and their nonclassical properties
In this paper we define a non-unitary displacement operator, which by acting
on the vacuum state of the pseudo harmonic oscillator (PHO), generates new
class of generalized coherent states (GCSs). An interesting feature of this
approach is that, contrary to the Klauder-Perelomov and Barut-Girardello
approaches, it does not require the existence of dynamical symmetries
associated with the system under consideration. These states admit a resolution
of the identity through positive definite measures on the complex plane. We
have shown that the realization of these states for different values of the
deformation parameters leads to the well-known Klauder-Perelomov and
Barut-Girardello CSs associated with the Lie algebra. This is why we
call them the generalized CSs for the PHO. Finally, study of some
statistical characters such as squeezing, anti-bunching effect and
sub-Poissonian statistics reveals that the constructed GCSs have indeed
nonclassical features.Comment: arXiv admin note: substantial text overlap with arXiv:1212.688
Approach of the Generating Functions to the Coherent States for Some Quantum Solvable Models
We introduce to this paper new kinds of coherent states for some quantum
solvable models: a free particle on a sphere, one-dimensional
Calogero-Sutherland model, the motion of spinless electrons subjected to a
perpendicular magnetic field B, respectively, in two dimensional flat surface
and an infinite flat band. We explain how these states come directly from the
generating functions of the certain families of classical orthogonal
polynomials without the complexity of the algebraic approaches. We have shown
that some examples become consistent with the Klauder- Perelomove and the
Barut-Girardello coherent states. It can be extended to the non-classical,
q-orthogonal and the exceptional orthogonal polynomials, too. Especially for
physical systems that they don't have a specific algebraic structure or
involved with the shape invariance symmetries, too.Comment: 16 page
Thermodynamics of Rotating Black Branes in Gauss-Bonnet-nonlinear Maxwell Gravity
We consider the Gauss-Bonnet gravity in the presence of a new class of
nonlinear electromagnetic field, namely, power Maxwell invariant. By use of a
suitable transformation, we obtain a class of real rotating solutions with
rotation parameters and investigate some properties of the solutions such as
existence of singularity(ies) and asymptotic behavior of them. Also, we
calculate the finite action, thermodynamic and conserved quantities of the
solutions and using the the Smarr-type formula to check the first law of
thermodynamics.Comment: 15 page
Charged Lifshitz Black Holes
We investigate modifications of the Lifshitz black hole solutions due to the
presence of Maxwell charge in higher dimensions for arbitrary and any
topology. We find that the behaviour of large black holes is insensitive to the
topology of the solutions, whereas for small black holes significant
differences emerge. We generalize a relation previously obtained for neutral
Lifshitz black branes, and study more generally the thermodynamic relationship
between energy, entropy, and chemical potential. We also consider the effect of
Maxwell charge on the effective potential between objects in the dual theory.Comment: Latex, 28 pages, 14 figures, some references adde
Einstein-Born-Infeld on Taub-NUT Spacetime in 2k+2 Dimensions
We wish to construct solutions of Taub-NUT spacetime in Einstein-Born-Infeld
gravity in even dimensions. Since Born-Infeld theory is a nonlinear
electrodynamics theory, in leads to nonlinear differential equations. However a
proper analytical solution was not obtain, we try to solve it numerically (by
the Runge-Kotta method) with initial conditions coinciding with those of our
previous work in Einstein-Maxwell gravity. We solve equations for 4, 6 and 8
dimensions and do data fitting by the least-squares method. For N=l=b=1, the
metric turns to the NUT solution only in 8 dimensions, but in 4 and 6
dimensions the spacetime does not have any Nut solution.Comment: 8 pages, 5 figure
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