Environmentally induced effects on a bipartite two-level system: Geometric phase and entanglement properties

FERNANDO C. LOMBARDO1, AND PAULA I. VILLAR

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Lugar: New York; Año: 2010 vol. 81 p. 221151 - 2211513

1050-2947

   We calculate the geometric phase of a bipartite two-level system coupled to an external environment. Weanalyze the reduced density matrix for an arbitrary initial state of the composite system and compute thecorrection to the unitary geometric phase through a kinematic approach. In all cases considered, we observe asimilar structure as a function of the degree of the entanglement of the initial state. Further, we compute theentanglement entropy and concurrence of the bipartite state and analyze if there is any relation among thesequantities and the geometric phase acquired during the nonunitary system’s evolution. Finally, we discuss theresults obtained.