Open quantum systems in thermal nonergodic environments

The dynamics of an open system crucially depends on the correlation function its environment, $C_B(t)$. We show that for thermal non-Harmonic environments $C_B(t)$ may not decay to zero but offset, $C_0>0$. presence such offset is determined by environment eigenstate structure, and whether it fulfills or thermalization hypothesis. Moreover, we a $C_0>0$ could render weak coupling approximation inaccurate prevent thermalize. Finally, realistic dye molecules, emergence using matrix product states (MPS), discuss link 1/f noise spectrum that, in contrast previous models, extends frequencies. Thus, our results be relevant describing dissipation quantum technological devices like superconducting qubits, which are known affected noise.