Near-field routing of hyperbolic metamaterials

Near-field light is invisible light at the subwavelength scale. Harnessed for a variety of practical applications, such as wireless power transfer, near-field light has an increasingly significant role in the development of miniature on-chip photonic devices. Controlling the direction of near-field light propagation has been an ongoing challenge that is of fundamental interest in photonics physics and can significantly advance a variety of applications.

So far, propagation of near-field light in a single direction is achieved by specific interactions between the electric dipole and the magnetic dipole in a system, which has led to inevitable complexities in device design. Hyperbolic metamaterials (HMMs), an important class of artificial anisotropic material with hyperbolic isofrequency contours, have attracted attention due to their unique ability to control near-field light by enabling subwavelength confinement of electromagnetic waves. Large wave-vector modes in HMMs are of particular interest because those modes are easier to integrate and have a smaller loss of energy at transfer.