Dyakonov plasmon polaritons, extending along the surfaces of a hyperbolic metamaterial

Plasmon polaritons of the Diakonov surface wave type along the flat boundary of a hyperbolic metamaterial with an arbitrary orientation of the crystallographic axis are considered. Conditions for the existence of fast, slow, flowing, gliding flowing, forward and backward plasmon polaritons are found. A waveguide in the form of an asymmetric layer of a hyperbolic metamaterial is considered. An expression for the density of electromagnetic energy in such a metamaterial is given.