Fermion localization and resonances on two-field thick branes

Abstract

We consider (4, 1)-dimensional branes constructed with two scalar fields $\ensuremath{\phi}$ and $\ensuremath{\chi}$ coupled to a Dirac spinor field by means of a general Yukawa coupling. The equation of motion for the coefficients of the chiral decomposition of the spinor in curved spacetime leads to a Schr\"odinger-like equation whose solutions allow to obtain the masses of the fermionic modes. The simplest Yukawa coupling $\overline{\ensuremath{\Psi}}\ensuremath{\phi}\ensuremath{\chi}\ensuremath{\Psi}$ is considered for the Bloch brane model and fermion localization is studied. We found resonances for both chiralities and related their appearance to branes with internal structure.