10 research outputs found
Entanglement dynamics in the Lipkin-Meshkov-Glick model
The dynamics of the one-tangle and the concurrence is analyzed in the
Lipkin-Meshkov-Glick model which describes many physical systems such as the
two-mode Bose-Einstein condensates. We consider two different initial states
which are physically relevant and show that their entanglement dynamics are
very different. A semiclassical analysis is used to compute the one-tangle
which measures the entanglement of one spin with all the others, whereas the
frozen-spin approximation allows us to compute the concurrence using its
mapping onto the spin squeezing parameter.Comment: 11 pages, 11 EPS figures, published versio
Classical diffusion of N interacting particles in one dimension: General results and asymptotic laws
I consider the coupled one-dimensional diffusion of a cluster of N classical
particles with contact repulsion. General expressions are given for the
probability distributions, allowing to obtain the transport coefficients. In
the limit of large N, and within a gaussian approximation, the diffusion
constant is found to behave as N^{-1} for the central particle and as (\ln
N)^{-1} for the edge ones. Absolute correlations between the edge particles
increase as (\ln N)^{2}. The asymptotic one-body distribution is obtained and
discussed in relation of the statistics of extreme events.Comment: 6 pages, 2 eps figure