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Updated: Sep 11, 2025
13:02
Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
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Mid-infrared topological cavity with valley edge modes
Applied Optics
|August 12, 2025
Summary
Topological valley photonic crystals enable robust, one-way light propagation for quantum cascade lasers (QCLs) and interband cascade lasers (ICLs). These photonic crystals offer defect-resilient cavities for advanced mid-infrared photonic devices.
Area of Science:
- Photonics
- Condensed Matter Physics
- Quantum Optics
Background:
- Quantum cascade lasers (QCLs) and interband cascade lasers (ICLs) are key mid-infrared light sources.
- Topological edge states (ESs) in photonic crystals offer robust, unidirectional light propagation.
- Valley photonic crystals (VPCs) utilize distinct domain properties for topological phenomena.
Purpose of the Study:
- Investigate topological valley photonic crystals for QCLs and ICLs.
- Demonstrate the application of valley-dependent ES for optical devices.
- Explore the performance of topological cavities in the presence of defects.
Main Methods:
- Theoretical investigation of topological edge states in VPCs.
- Simulation of optical propagation and cavity properties.
- Analysis of defect tolerance in topological cavities.
Main Results:
- Valley-dependent ES provide topological protection for one-way optical propagation.
- Topologically protected triangular cavities exhibit high quality factors and uniform energy distribution.
- TE and TM mode cavities show distinct characteristics, enabling tailored laser development.
Conclusions:
- VPCs offer a robust platform for mid-infrared photonic devices using QCLs and ICLs.
- Topological protection enhances device reliability against defects.
- Tunable cavity properties allow for application-specific topological laser designs.
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