Crystallographic directions 1 Dispersion relations 1 Effective medium approaches 1 Electromagnetic simulation 1 Finite difference time domain method 1 Hybridisation 1 Matrix display 1 Metamaterials 1 Molybdenum oxide 1 New branches 1 Phonons 1 Photons 1 Polariton dispersion 1 Reststrahlen band Sub-wavelength 1 Surface phonon-polaritons 1