Dynamics of two central spins immersed in spin baths

In this article we derive the exact dynamics of a two-qubit (spin 1/2) system interacting centrally with separate spin baths composed of qubits in a thermal state. Furthermore, each spin of the bath is coupled to every other spin of the same bath. The corresponding dynamical map is constructed. It is used to analyze the non-Markovian nature of the two qubit central spin dynamics. We further observe the evolution of quantum correlations like entanglement and discord under the influence of the environmental interaction. Moreover, we demonstrate the comparison between this exact two-qubit dynamics and the locally acting central spin model in a spin bath. This work is a stepping stone towards the realization of non-Markovian heat engines and other quantum thermal devices.

Automated summary

In this article, we derive the dynamics of a two-qubit system interacting with spin baths composed of qubits in a thermal state. We analyze the non-Markovian nature of the two qubit dynamics and observe the evolution of quantum correlations under the influence of environmental interaction. We also compare the exact two-qubit dynamics with a locally acting central spin model in a spin bath. This work is important for realizing non-Markovian heat engines and other quantum thermal devices.