▎ 摘　　要

A planar graphene-based heterostructure is considered, which behaves differently: as a barrier or a quantum well at small or large momenta of charge carriers, respectively. This heterostructure contains a strip of gapped graphene with a lower Fermi velocity, surrounded by gapless graphene with a higher Fermi velocity. In this configuration, an interface state arises at the intersection point of dispersion curves. The transformation of this interface state into a fundamental bound state is investigated.