Terahertz Optoelectronic Devices Based on Three-Dimensional Modelling of Symmetrically Coupled Surface Plasmon Polariton Resonances in Bulk Dirac Semimetal

Abstract

Bulk Dirac Semimetal (BDS) - a three-dimensional counterpart of graphene, prominently known for its topologically protected linear dispersion energy bands embraces remarkable plasmonic responses at terahertz (THz) frequencies, which can be well capitalized for its optoelectronic applications. Recently, we have demonstrated the BDS based THz plasmonic applications such as surface plasmon polariton assisted microparticle sensing, THz waveguiding with curved/bending geometries and all-optical THz logic gates. However, all of the demonstrations were restricted with 2-D BDS geometries where height of the BDS was assumed to be infinity. For practical applications, it is essential to consider the height dimension in device realization. In this work, we demonstrate 3-D numerical modelling results of BDS based THz applications by considering height dimension of the BDS in the design of curved waveguides, sub-wavelength waveguiding in tapered geometries and 3-D XOR logic gate. We anticipate that the above findings manifest BDS as a potential candidate for opening new avenues in the realization of THz optoelectronic devices.

Keywords

• bulk dirac semimetal (bds)
• sub-wavelength waveguiding
• thz logic gate
• 3-dimensional
• surface plasmon polariton (spp)