Entanglement temperature in molecular magnets composed of -spin dimersD. O. Soares-Pinto1, 2, A. M. Souza3, R. S. Sarthour2, I. S. Oliveira2, M. S. Reis4, P. Brandão4, 5, J. Rocha4, 5 and A. M. dos Santos6
1 Instituto de Física de São Carlos, Universidade de São Paulo - P.O. Box 369, 13560-970, São Carlos, SP, Brazil
2 Centro Brasileiro de Pesquisas Físicas - Rua Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, Brazil
3 Institute for Quantum Computing and Department of Physics and Astronomy, University of Waterloo Waterloo, Ontario, N2L 3G1, Canada
4 CICECO, Universidade de Aveiro - 3810-193, Aveiro, Portugal, EU
5 Departamento de Química, Universidade de Aveiro - 3810-193 Aveiro, Portugal, EU
6 NSSD, ORNL - Oak Ridge, TN 37831-6475, USA
received 4 May 2009; accepted in final form 17 August 2009; published August 2009
published online 15 September 2009
In the present work, we investigate the quantum thermal entanglement in molecular magnets composed of dimers of spin S, using an Entanglement Witness built from measurements of magnetic susceptibility. An entanglement temperature, Te, is then obtained for some values of spin S. From this, it is shown that Te is proportional to the intradimer exchange interaction J and that entanglement appears only for antiferromagnetic coupling. The results are compared to experiments carried on three isostructural materials: (M=Mn, Fe or Cu).
03.67.Mn - Entanglement measures, witnesses, and other characterizations.
75.50.Xx - Molecular magnets.
03.67.Bg - Entanglement production and manipulation.
© EPLA 2009