Quantum processes can be described in terms of a quasiprobability distribution (the Wigner distribution) analogous to the phase-space probability distribution of the classical realm. In contrast to the incomplete glimpse of the wave function that is achievable in a single shot experiment, the Wigner distribution, accessible by quantum state tomography, reflects the full quantum state. We show that during the fundamental symmetry-breaking process of a generic quantum system, with a symmetry-breaking field driving the quantum system far from equilibrium, the Wigner distribution evolves continuously with the system undergoing a sequence of revivals into the symmetry-unbroken state, followed by collapses onto a quasiclassical state akin to the one realized in infinite-size systems. We show that generically this state is completely delocalized both in momentum and in real space. Â© 2013 American Physical Society.
|Titolo:||Quantum collapses and revivals of matter wave in dynamics of symmetry breaking|
|Data di pubblicazione:||2013|
|Appare nelle tipologie:||1.1 Articoli su Rivista|