  We explore the features of an equally-spaced array of two-level quantum
emitters, that can be either natural atoms (or molecules) or artificial atoms,
coupled to a field with a single continuous degree of freedom (such as an
electromagnetic mode propagating in a waveguide). We investigate the existence
and characteristics of bound states, in which a single excitation is shared
among the emitters and the field. We focus on bound states in the continuum,
occurring in correspondence of excitation energies in which a single excited
emitter would decay. We characterize such bound states for an arbitrary number
of emitters, and obtain two main results, both ascribable to the presence of
evanescent fields. First, the excitation profile of the emitter states is a
sinusoidal wave. Second, we discuss the emergence of multimers, consisting in
subsets of emitters separated by two lattice spacings in which the
electromagnetic field is approximately vanishing.
