Sudden change of quantum discord for a system of two qubits

It is known that quantum discord might experience a sudden transition in its dynamics when calculated for certain Bell-diagonal states (BDS) that are in interaction with their surroundings. We examine this phenomenon, known as the sudden change of quantum discord, considering the case of two qubits independently interacting with dephasing reservoirs. We first demonstrate that, for a class of initial states which can be chosen arbitrarily close to BDS, the transition is in fact not sudden, although it might numerically appear so if not studied carefully. Then, we provide an extension of this discussion covering the X-shaped density matrices. Our findings suggest that the transition of quantum discord might be sudden only for an highly idealized zero-measure subset of states within the set of all possible initial conditions of two qubits. © 2013 American Physical Society.

Programa de trabajo estadístico internacional para América Latina y el Caribe, 1997-1998: Subprograma 1: adaptación y producción de estadísticas básicas en el marco de una estrategia regional para la implementación del Sistema de Cuentas Nacionales 1993 (SCN 1993) = Programme of international statistical work for Latin America and the Caribbean, 1997-1998: Subprogramme 1: adaptation and production of basic statistics in the framework of a regional strategy for the implementation of the System of National Accounts 1993 (SCN 1993)

Incluye Bibliografía

Informe del Seminario Regional de Expertos sobre Comparaciones del Sistema de Cuentas Nacionales y del Sistema de Balances de la Economía Nacional en América Latina = Report of the Regional Seminar of Experts on Comparisons of the System of National Accounts and the System of Balances of the National Economy in Latin America

Incluye Bibliografía

Informe del Seminario sobre el Sistema Uniforme de Estadísticas de Transporte Marítimo = Report of the Seminar on the Uniform System of Maritime Transport Statistics

Presenta la organizacion, el resumen de las presentaciones y las resoluciones adoptadas en el seminario que tuvo como objetivo facilitar la aplicacion de un sistema uniforme de estadisticas de transporte maritimo en America Latina y el Caribe.

Status of implementation of the System of National Accounts (SNA) 1993 in selected Caribbean countries

Includes bibliography