IFEG 20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
The Loschmidt Echo as a decoherence quantifier for many-body systems
Autor/es:
PABLO RENÉ ZANGARA; AXEL DAMIÁN DENTE; PATRICIA R. LEVSTEIN; HORACIO MIGUEL PASTAWSKI
Lugar:
La Falda
Reunión:
Workshop; XII encuentro Superficies y Materiales nanoestructurados 2012; 2012
Institución organizadora:
IFEG - CONICET
Resumen:
The coherent control of many-body quantum processes is a fundamental challenge for quantum information processing. The minimization of decoherence, or quantum interference degradation, turns to be a crucial task. In recent years, the Loschmidt Echo (LE), which is based on time reversal experiments, has been employed as a decoherence quantifier. In this work, we consider two spin chains with planar Hamiltonians, which are weakly coupled by a general interaction, including Ising and planar terms. Only the Hamiltonian in one of the chains is inverted, and thus the Loschmidt Echo smoothly degrades. Several regimes are identified, and particularly we analyze the exponential decoherence described by a Fermi Golden Rule. Accordingly, decoherence rates are obtained and analyzed separately for each physical process present in the inter chain interaction. High efficiency in the many-body simulation for spin systems is enabled due to the use of Graphical Processing Units.
