Tunable 3D Dirac-semimetals supported mid-IR hybrid plasmonic waveguides

Based on 3D Dirac-semimetal (DSM) modified hybrid waveguides, tunable propagation properties have been investigated, including the effects of Fermi levels, structural parameters, and operation frequency. The results show that if the operation frequency is smaller (larger) than the transition frequency (hw approximate to 2 vertical bar mu(c)), the proposed hybrid waveguides indicate strong (weak) confinement because the DSM layer manifests a high plasmonic (dielectric low) loss property. The dielectric fiber shape affects the propagation property obviously, as the elliptical parameter decreases, the confinement and figure of merit increase, and the loss reduces. With the increase in Fermi level, the propagation constant increases, and the frequency (amplitude) modulation depth is 32.31% (12.93%) if the Fermi level changes in the range of 0.01-0.15 eV. The results are very helpful in understanding the tunable mechanisms of hybrid wave-guides and designing novel plasmonic devices in the future, e.g., modulators, filters, lasers, and resonators. (C) 2021 Optical Society of America

Automated summary

The research on tunable propagation properties of hybrid waveguides based on 3D Dirac-semimetal (DSM) modification reveals significant effects of structural parameters and operation frequency. By adjusting the Fermi levels and dielectric fiber shape, the hybrid waveguides can exhibit enhanced confinement and reduced loss, providing potential for designing novel plasmonic devices.