In the theory of solid-state physics [1], quantum field theory [2] and statistical physics [3,4] are arise the problems related with the standard or "truncated" spin-boson models. In a well-known model of radiative decay (the so-called spin-boson model) it is assumed that an atom, which can be in two states - ground state with energy - and excited state with energy - emits and absorbs photons, going over from one state to the other [4-7].