Violation of the Bell inequality for thermal states of interaction qubits investigated via a multi-qubit Heisenberg model

Xiaoguang Wang
2002 New Journal of Physics  
We study the violations of Bell inequality for thermal states of qubits in a multi-qubit Heisenberg model as a function of temperature and external magnetic fields. Unlike the behaviors of the entanglement the violation can not be obtained by increasing the temperature or the magnetic field. The threshold temperatures of the violation are found be less than that of the entanglement. We also consider a realistic cavity-QED model which is a special case of the mutli-qubit Heisenberg model.
doi:10.1088/1367-2630/4/1/311 fatcat:slztwur7yjc4rnanq6tw77fmx4