Full control of density of states in integrated hyperbolic metamaterial waveguides

In this work, we have investigated the possibility of controlling the photonic density of states in integrated hyperbolic metamaterial waveguide. For that purpose, we explicitly derive mode counting approach, which is suitable for calculating PDOS in metallic-cladded waveguides with anisotropic core. Within the course of this study, we demonstrate that the application of tunable graphene-based HMM as a waveguide core may result in complete control over photonic density of states seen by an electric dipole of arbitrary orientation, located inside the waveguide. In particular, we have shown that very strong enhancement, up to 3 orders of magnitude, or complete suppression of PDOS may be obtained for the given light polarization (TE or TM modes). Moreover, by engineering material and/or structural parameters of HMM, it is possible to obtain all discussed effects on the emission spectrum of almost any dipole operating within infrared spectral range.