  Cavity array metamaterials (CAMs), composed of optical microcavities in a
lattice coupled via tight-binding interactions, represent a novel architecture
for engineering metamaterials. Since the size of the CAMs' constituent elements
are commensurate with the operating wavelength of the device, it cannot
directly utilise classical transformation optics in the same way as traditional
metamaterials. By directly transforming the internal geometry of the system,
and locally tuning the permittivity between cavities, we provide an alternative
framework suitable for tight-binding implementations of metamaterials. We
develop a CAM-based cloak as the case study.
