Tunable multimode and narrowband in a photonic quasicrystal waveguide

Area of Science:

• Photonics
• Materials Science
• Waveguide Optics

Background:

• Photonic quasicrystal waveguides offer unique light manipulation properties.
• Quasiperiodic multilayer structures enable the formation of multiple omnidirectional photonic band gaps (PBGs).
• Controlling light propagation in waveguides is crucial for optical device miniaturization.

Purpose of the Study:

• To propose and investigate a novel photonic quasicrystal waveguide design.
• To demonstrate the existence and tunability of multiple omnidirectional PBGs.
• To explore the potential for enhanced waveguide performance and novel optical device applications.

Main Methods:

• Utilizing a hollow core surrounded by coaxial dielectric quasiperiodic multilayer cladding.
• Analyzing the self-similarity in the cladding structure to identify omnidirectional PBGs.
• Investigating the tunability of PBG center frequency and width via refractive index and quasiperiodic sequence generation.

Main Results:

• Multiple omnidirectional PBGs were observed in the proposed waveguide structure.
• Light waves within PBGs are totally reflected, enabling multimode transport.
• Tunability of PBG properties was demonstrated by altering refractive indexes and quasiperiodic sequence generations.
• Enhanced quality factor and confinement performance were achieved by narrowing PBGs.

Conclusions:

• The proposed photonic quasicrystal waveguide facilitates efficient multimode transport through tunable omnidirectional PBGs.
• The design allows for significant enhancement of waveguide quality factor and light confinement.
• This research paves the way for miniaturized, multifunctional optical devices like on-chip filters and laser resonators.