TY - JOUR
AB - © 2014 American Physical Society. A bipartite state ?AB is symmetric extendible if there exists a tripartite state ?ABB? whose AB and AB? marginal states are both identical to ?AB. Symmetric extendibility of bipartite states is of vital importance in quantum information because of its central role in separability tests, one-way distillation of Einstein-Podolsky-Rosen pairs, one-way distillation of secure keys, quantum marginal problems, and antidegradable quantum channels. We establish a simple analytic characterization for symmetric extendibility of any two-qubit quantum state ?AB; specifically, tr(?B2)?tr(?AB2)-4det?AB. As a special case we solve the bosonic three-representability problem for the two-body reduced density matrix.
AU - Chen, J
AU - Ji, Z
AU - Kribs, D
AU - Lütkenhaus, N
AU - Zeng, B
DA - 2014/09/17
DO - 10.1103/PhysRevA.90.032318
JO - Physical Review A - Atomic, Molecular, and Optical Physics
PY - 2014/09/17
TI - Symmetric extension of two-qubit states
VL - 90
Y1 - 2014/09/17
Y2 - 2019/11/21
ER -