The Semiclassical Tool in Complex Physical Systems:

RODOLFO A. JALABERT; HORACIO M. PASTAWSKI

Advances in Solid State Physics vol. 41

Springer

Lugar: Heidelberg; Año: 2001; p. 486 - 496

The Semiclassical Tool in Complex Physical Systems:            Mesoscopics and Decoherence             R. Jalabert and H. M. Pastawski             in Advances in Solid State Physics Vol. 41,  Kramer, B., (Ed.) pp. 483 - 496, Springer Verlag (Heidelberg, 2001).  ISBN 3-540-42000-2           http://link.springer.de/link/service/series/4636/tocs/t1041.htm Semiclassical methods have been extensively used in a variety of physical problems, ranging from nuclear to cluster physics and from ballistic transport to interaction effects in nanostructures. We present a few physical examples in order to illustrate the way in which semiclassics can be adapted to deal with complex problems. Special emphasis is devoted to the problem of decoherence. When a one-particle system, whose classical correspondent is chaotic, evolves coupled to a weak quenched environment, we can show that the decoherence rate is asymptotically given by the mean Lyapunov exponent. Its independence of the perturbation strength, within a given range, is consistent with numerical simulations and recent experiments of spin echo in nuclear magnetic resonance.