We show that the time dependence of correlation functions in an extended quantum system in d dimensions, which is prepared in the ground state of some Hamiltonian and then evolves without dissipation according to some other Hamiltonian, may be extracted using methods of boundary critical phenomena in d+1 dimensions. For d=1 particularly powerful results are available using conformal field theory. These are checked against those available from solvable models. They may be explained in terms of a picture, valid more generally, whereby quasiparticles, entangled over regions of the order of the correlation length in the initial state, then propagate classically through the system.
|Titolo:||Time dependence of correlation functions following a quantum quench|
|Autori:||Calabrese P; Cardy J|
|Data di pubblicazione:||2006|
|Digital Object Identifier (DOI):||10.1103/PhysRevLett.96.136801|
|Appare nelle tipologie:||1.1 Journal article|