In this paper, the Casimir energy density, loop corrections, and generation of topological mass are investigated for a system consisting of two interacting real and complex scalar fields. The interaction considered is the quartic interaction in the form of a product of the modulus square of the complex field and the square of the real field. In addition, it is also considered the self-interaction associated with each field. In this theory, the scalar field is constrained to always obey periodic condition, while the complex field obeys in one case a quasiperiodic condition and in the other case mixed boundary conditions. The Casimir energy density, loop corrections, and topological mass are evaluated analytically for the massive and massless scalar fields considered. An analysis of possible different stable vacuum states and the corresponding stability condition is also provided. In order to better understand our investigation, some graphs are also presented. The formalism we use here to perform such investigation is the effective potential, which is written as loop expansions via path integral in quantum field theory.
