Scattering-free energy storage in open cavities bounded by metasurfaces

摘要

The storage of electromagnetic energy is a typical capability of closed cavities, whose impenetrable walls do not allow energy leakage in the form of electromagnetic radiation. Recently, the interest in open or partially-open cavities able to absorb and store the energy carried by an external illuminating field has stimulated research efforts in the exploration of special cavities exhibiting anomalous scattering properties. In this contribution, we investigate the scattering properties of a partially open cavity, bounded on one side by an infinite reflector and on the other side by an infinite metasurface. We show that for a specific illumination signal, the cavity may operate in its virtual absorption state, exhibiting no reflection nor transmission. Being the system lossless, the impinging energy is totally stored in the cavity between the metallic reflector and the metasurface. The proposed structure, which can be easily implemented, may enable the design of lossless systems with dynamic energy properties.