Eur. Phys. J. D 39, 313-320 (2006)
https://doi.org/10.1140/epjd/e2006-00087-1

Quantum phase transition of entanglement in Heisenberg spin model with quantized field

¹ Institute of Theoretical Physics, Shanxi University, Taiyuan, 030006, P.R. China
² Institute of Condensed Matter Physics, Linyi Normal University, Linyi, 276005, P.R. China
³ Department of Physics, Qufu Normal University, Qufu, 273165, P.R. China
⁴ Department of Physics, Shaoxing College of Arts and Sciences, Shaoxing, 312000, P.R. China

Corresponding author: ^a hemm@sxu.edu.cn

Received: 13 September 2005
Revised: 3 December 2005
Published online: 20 April 2006

Abstract

In this paper, we investigate the entanglement of a two-spin system with Heisenberg exchange interaction in a quantized field. The pairwise entanglement between bipartite subsystems is obtained. It is shown that the entanglement exhibits a quantum phase transition due to the variation of exchang coupling. Phase diagrams are obtained explicitly. The analogy of the quantum phase transition compared to the case under a classical field are addressed.