On Dyakonov–Voigt surface waves guided by the planar interface of dissipative materials

Dyakonov–Voigt (DV) surface waves guided by the planar interface of (i) material A, which is a uniaxial dielectric material specified by a relative permittivity dyadic with eigenvalues ε_A ^s and ε_A ^t , and (ii) material B, which is an isotropic dielectric material with relative permittivity ε_B, are numerically investigated by solving the corresponding canonical boundary-value problem. The two partnering materials were generally dissipative, with the optic axis of material A being inclined at the angle χ ∈ [0^◦, 90^◦] relative to the interface plane. No solutions of the dispersion equation for DV surface waves exist when χ = 90^◦. Also, no solutions exist for χ ∈ (0^◦, 90^◦), when both partnering materials are nondissipative. For χ ∈ [0^◦, 90^◦), the degree of dissipation of material A has a profound effect on the phase speeds, propagation lengths, and penetration depths of the DV surface waves. For mid-range values of χ, DV surface waves with negative phase velocities were found. For fixed values of ε_A ^s and ε_A ^t in the upper-half-complex plane, DV surface-wave propagation is only possible for large values of χ when |ε_B| is very small.