Quantum fluctuations of the ultracold atom-molecule mixtures

We investigate evolution of the quantum coherence in the ultracold mixture of fermionic atoms and bosonic dimer molecules. Interactions are there experimentally controlled via tuning the external magnetic field. Consequently, the fermionic atoms and their bosonic counterparts can be driven to a behavior resembling the usual BCS to BEC crossover. We analyze in some detail how this quantum coherence evolves with respect to time upon a smooth and abrupt sweep across the Feshbach resonance inducing the atom-molecule quantum fluctuations.