11,651 research outputs found
A single atom-based generation of Bell states of two cavities
A new conditional scheme for generating Bell states of two spatially
separated high-Q cavities is reported. Our method is based on the passage of
one atom only through the two cavities. A distinctive feature of our treatment
is that it incorporates from the very beginning the unavoidable presence of
fluctuations in the atom-cavity interaction times. The possibility of
successfully implementing our proposal against cavity losses and atomic
spontaneous decay is carefully discussed
Elementary symmetric functions of two solvents of a quadratic matrix equation
Quadratic matrix equations occur in a variety of applications. In this paper
we introduce new permutationally invariant functions of two solvents of the n
quadratic matrix equation X^2- L1X - L0 = 0, playing the role of the two
elementary symmetric functions of the two roots of a quadratic scalar equation.
Our results rely on the connection existing between the QME and the theory of
linear second order difference equations with noncommutative coefficients. An
application of our results to a simple physical problem is briefly discussed.Comment: 20 page
Interaction of bimodal fields with few-level atoms in cavities and traps
The spectacular experimental results of the last few years in cavity quantum
electrodynamics and trapped ions research has led to very high level laboratory
performances. Such a stimulating situation essentially stems from two decisive
advancements. The first is the invention of reliable protocols for the
manipulation of single atoms. The second is the ability to produce desired
bosonic environments on demand. These progresses have led to the possibility of
controlling the form of the coupling between individual atoms and an arbitrary
number of bosonic modes. As a consequence, fundamental matter-radiation
interaction models like, for instance, the JC model and most of its numerous
nonlinear multiphoton generalizations, have been realized or simulated in
laboratory and their dynamical features have been tested more or less in
detail. This topical paper reviews the state of the art of the theoretical
investigations and of the experimental observations concerning the dynamical
features of the coupling between single few-level atoms and two bosonic modes.
In the course of the paper we show that such a configuration provides an
excellent platform for investigating various quantum intermode correlation
effects tested or testable in the cavity quantum electrodynamics and trapped
ion experimental realms. In particular we discuss a mode-mode correlation
effect appearing in the dynamics of a two-level atom quadratically coupled to
two bosonic modes. This effect, named parity effect, consists in a high
sensitivity to the evenness or oddness of the total number of bosonic
excitations.Comment: Topical Review. To appear on J. Mod. Op
Revealing non-classical behaviours in the oscillatory motion of a trapped ion
The possibility of revealing non-classical behaviours in the dynamics of a
trapped ion via measurements of the mean value of suitable operators is
reported. In particular we focus on the manifestation known as `` Parity
Effect\rq\rq which may be observed \emph{directly measuring} the expectation
value of an appropriate correlation operator. The experimental feasibility of
our proposal is discussed.Comment: 5 pages, 2 figure
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