Laurent Bruneau (Univ. Cergy)
Repeated interactions quantum systems. (mp_arc/05-376)
Joint work with Alain Joye (Univ. Grenoble) and Marco Merkli (MUN-St.
John's, Canada).
A quantum system S interacts in a successive way with the elements E of
a chain of identical and independant quantum subsystems. Each
interaction lasts
for a duration T and is governed by a fixed coupling between S and E.
We show that, in the limit of large times, the system approaches an
asymptotic
state which is T-periodic, depend on the initial state of the chain but
not of the system S. If the chain is initially at thermal equilibrium,
then
the asymptotic state satisfies an average 2nd law of thermodynamics.