Interaction-disorder competition in a spin system evaluated through the Loschmidt echo

PABLO ZANGARA; AXEL D. DENTE; ANÍBAL IUCCI; H. M. PASTAWSKI

PHYSICAL REVIEW B - SOLID STATE

American Physical Society

Lugar: new york; Año: 2013 vol. 88 p. 19510 - 19513

0556-2805

PHYSICAL REVIEW B 88, 195106 (2013)Interaction-disorder competition in a spin system evaluated through the Loschmidt echoP.R. Zangara, A.D. Dente, A. Iucci, P.R. Levstein,and H.M. PastawskiThe interplay between interactions and disorder in closed quantum many-body systems is relevant for thermalization phenomenon. In this paper, we address this competition in an infinite temperature spin system by means of the Loschmidt echo (LE), which is based on a time reversal procedure. This quantity has been formerly employed to connect quantum and classical chaos, and in the present many-body scenario we use it as a dynamical witness.We assess the LE time scales as a function of disorder and interaction strengths. The strategyenables a qualitative phase diagram that shows the regions of ergodic and nonergodic behavior of the polarization under the echo dynamics.DOI: 10.1103/PhysRevB.88.195106