Photonic defect modes in cholesteric liquid crystal resonators with embedded isotropic layers

Area of Science:

• Photonics
• Soft Matter Physics
• Materials Science

Background:

• Photonic defect modes offer high Q-factors and local density of states, useful for nonlinearity enhancement, lasing, and cavity quantum electrodynamics.
• These modes are sensitive to structural changes, requiring precise control for desired resonance frequencies.
• Cholesteric liquid crystals (CLCs) provide a tunable platform for photonic applications.

Purpose of the Study:

• To investigate photonic defect modes in a structure with an isotropic layer embedded between two CLC layers.
• To analyze the influence of geometrical and material parameters on defect mode eigenfrequencies and Q-factors.
• To explore the potential of these defect modes for topological soft matter photonics and directional light emission.

Main Methods:

• Full electrodynamics numerical simulations were employed.
• Analysis included transmission spectra and electric field profiles of defect modes.
• Investigated the impact of refractive indices, thicknesses, and boundary anchoring conditions.

Main Results:

• Characterized photonic defect modes within and around the photonic bandgap.
• Demonstrated the tunability of eigenfrequencies and Q-factors by varying structural parameters.
• Established a connection between these defect modes and previously studied twist defect modes.
• Presented eigenmodes in asymmetric resonators for directional light emission.

Conclusions:

• Photonic defect modes in CLC-based structures are promising for advanced photonic applications.
• Precise control over structural and material parameters enables tailoring of defect mode properties.
• This research contributes to the design of topological soft matter photonics, potentially enabling defect mode lasing in CLC geometries.