Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/148910

Title

Conservation rules for entanglement transfer between qubits

Author(s)

Chan, Stanley;  Reid, M. D.;  Ficek, Z.

Abstract

We consider an entangled but non-interacting qubit pair a1 and b1 that is independently coupled to a set of local qubit systems, aI and bJ, of 0 bit value, respectively. We derive rules for the transfer of entanglement from the pair a1–b1 to an arbitrary pair aI–bJ, for the case of qubit-number conserving local interactions. It is shown that the transfer rule depends strongly on the initial entangled state. If the initial entanglement is in the form of the Bell state corresponding to anti-correlated qubits, the sum of the square of the nonlocal pairwise concurrences is conserved. If the initial state is the Bell state with correlated qubits, this sum can be reduced, even to zero in some cases, to reveal a complete and abrupt loss of all nonlocal pairwise entanglement. We also identify that for the nonlocal bipartitions A–bJ involving all qubits at one location, with one qubit bJ at the other location, the concurrences satisfy a simple addition rule for both cases of the Bell states that the sum of the square of the nonlocal concurrences is conserved.

Publication type

Journal article

Research centre

Swinburne University of Technology

Source

Journal of Physics B: Atomic, Molecular and Optical Physics, Vol. 43, no. 21 (2010)

Publication year

2010

FOR Code(s)

0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics;  0205 Optical Physics

Keyword(s)

Conservation rules;  Entanglement transfer;  Qubits

Publisher

Institute of Physics Publishing

ISSN

0953-4075

Publisher URL

http://dx.doi.org/10.1088/0953-4075/43/21/215505

Copyright

Copyright © 2010 IOP Publishing.

Peer reviewed