Quantum fidelity and Von Neumann entropy of a Bose-Fermi mixture in 1D double well potential

Abstract

Abstract The time evolution of probability density, the ground-state fidelity and the entanglement of a Bose-Fermi mixture in a 1D double well potential, are studied through the two-mode approximation. We found that the behavior of the quantum return probability shows three distinct regions. The first region is characterized by a complete miscibility, and correlated tunneling of bosons and fermion. The second region is characterized by correlated sequential tunneling and in the last region we found an increase in the tunneling frequency of the two species. Through the Von Neumann entropy, we found that the boson-fermion coupling allows a maximum entanglement of quantum correlations of bosons and fermions in the same value. Finally, Considering variations in the interaction between pairs of fermions λ FF , pairs of bosons λ BB , and variations in the interaction between particles of different species λ BF , we calculated the fidelity in the λ FF − λ BF and λ BB − λ BF planes and we found that the drop of the two fidelities becomes deeper and deeper as the boson-fermion interaction decreases.