Decoherence time in self-induced decoherence

A general method for obtaining the decoherence time in self-induced decoherence is presented. In particular, it is shown that such a time can be computed from the poles of the resolvent or of the initial conditions in the complex extension of the Hamiltonian’s spectrum. Several decoherence times are estimated: ${10}^{-13}–{10}^{-15}\mathrm{s}$ for microscopic systems, and ${10}^{-37}–{10}^{-39}\mathrm{s}$ for macroscopic bodies. For the particular case of a thermal bath, the order of magnitude of our results agrees with that obtained by the einselection (environment-induced decoherence) approach.