Broadly tunable one-way terahertz plasmonic waveguide based on nonreciprocal surface magneto plasmons

Area of Science:

• Terahertz (THz) photonics
• Plasmonics
• Condensed matter physics

Background:

• Existing one-way plasmonic devices often rely on surface plasmon interference.
• Achieving tunable, one-way propagation in subwavelength waveguides remains a challenge.

Purpose of the Study:

• To propose and theoretically demonstrate a novel one-way-propagating, broadly tunable terahertz plasmonic waveguide.
• To explore the use of nonreciprocal surface magnetoplasmons for unidirectional wave propagation.

Main Methods:

• Theoretical modeling of a metal-dielectric-semiconductor structure.
• Numerical simulations to verify waveguide performance and tunability.
• Investigation of the role of external magnetic fields on surface magnetoplasmons.

Main Results:

• Demonstrated a subwavelength waveguide exhibiting one-way propagation.
• Showcased broad tunability of the one-way frequency band by adjusting external magnetic fields.
• Confirmed the mechanism relies on nonreciprocal surface magnetoplasmons, not interference effects.

Conclusions:

• The proposed metal-dielectric-semiconductor structure offers a new platform for tunable one-way terahertz wave propagation.
• This concept paves the way for high-performance, compact tunable plasmonic devices like isolators, switches, and splitters for integrated circuits.