  SQUID (Superconducting QUantum Interference Device) metamaterials, subject to
a time-independent (dc) flux gradient and driven by a sinusoidal (ac) flux
field, support chimera states that can be generated with zero initial
conditions. The dc flux gradient and the amplitude of the ac flux can control
the number of desynchronized clusters of such a generated chimera state (i.e.,
its `heads') as well as their location and size. The combination of three
measures, i.e., the synchronization parameter averaged over the period of the
driving flux, the incoherence index, and the chimera index, is used to predict
the generation of a chimera state and its multiplicity on the parameter plane
of the dc flux gradient and the ac flux amplitude. Moreover, the full-width
half-maximum of the distribution of the values of the synchronization parameter
averaged over the period of the ac driving flux, allows to distinguish chimera
states from non-chimera, partially synchronized states.
