Directive and coherent thermal emission of hybrid surface plasmon-phonon polaritons in n-GaN gratings of linear and radial shapes

• DOI: 10.1364/ome.494777
• Publication Date: 2023-08-10T10:00:10Z
• Authors: Vytautas Janonis; Jacek Kacperski; Algirdas Selskis; Roman M. Balagula; Pawel Prystawko; Irmantas Kašalynas
• Keywords: Surface phonon

Beaming and coherent thermal emission of the hybrid surface plasmon phonon polaritons (SPPhPs) was numerically experimentally investigated employing n-GaN relief gratings (SRGs) shaped in a linear radial geometry. The polariton propagation losses were minimized with help rigorous coupled wave analysis model, while spatial temporal quality selected mode radiation normal direction maximized by fixing grating period value at 17.5 µm varying filling factor from 75% to 25%. A set optimal design geometry SRG samples fabricated order validate characteristics SPPhPs found numerical modeling. We demonstrated that both efficient beaming are possible achieve through excitation interference same number but opposite sign modes SRG.