Fisher information and quantum state estimation of two-coupled atoms in presence of two external magnetic fields

Abstract

We consider a quantum system of an atom-atom interaction in the presence of two external magnetic and classical fields in x, and z directions. The dynamical behavior of single atom quantum quantifiers such as the atomic Wehrl entropy, atomic Fisher information and quantum entropy are investigated. The quantum entanglement degradation in regard to the atomic state estimation are discussed through the evolution of the atomic Fisher information flow, and the effects of the external classical fields and types of time dependent coupling between the two atoms are examined. We explore the relationship between different statistical quantities in the absence and presence of classical field during the time evolution. The results show that the creation and manipulation of entanglement by external fields greatly benefit within the suitable choice of the kind of time dependent coupling among the two atoms and external.