Nonclassical analogs of solitons in quantum field theory

The possible existence of a series of quantum copies of classical soliton solutions is discussed, which don't exist when the effective Planck constant of the theory $\gamma$ tends to zero. Within the conventional weak coupling expansion in $\sqrt {\gamma }$ such non-classical solitons are of order $O(\sqrt {\gamma })$ in energy and therefore lie in between the true classical solutions and true secondary quantized excitations. The analytic results concerning the shape functions, masses and stability properties of such excitations are given for $\varphi ^4$-kink theory.