Eur. Phys. J. D 25, 293-298 (2003)
https://doi.org/10.1140/epjd/e2003-00243-1

Robustness of entanglement for Bell decomposable states

¹ Department of Theoretical Physics and Astrophysics, Tabriz University, Tabriz 51666, Iran
² Institute for Studies in Theoretical Physics and Mathematics, Tehran 19395-1795, Iran
³ Research Institute for Fundamental Sciences, Tabriz 51666, Iran

Corresponding authors: ^a akhtarshenas@tabrizu.ac.ir - ^b jafarizadeh@tabrizu.ac.ir

Received: 3 August 2002
Revised: 28 October 2002
Published online: 5 August 2003

Abstract

We propose a simple geometrical approach for finding robustness of entanglement for Bell decomposable states of two-qubit quantum systems. It is shown that for these states robustness is equal to the concurrence. We also present an analytical expression for two separable states that wipe out all entanglement of these states. Random robustness of these states is also obtained. We also obtain robustness of a class of states obtained from Bell decomposable states via some special local operations and classical communications (LOCC).