Band Gap Engineering and Light Localization in Si and InP Based Three-dimensional Photonic Crystals
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2025-08-29 |
| Journal | American Journal of Optics and Photonics |
| Authors | Fairuz Aniqa Salwa, Jahirul Khandaker, Mohammad Aminul Islam, Md. Abdur Rahman, Md Minhaz Chowdhury |
| Institutions | Jahangirnagar University |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: 3D Photonic Crystal Engineering
Section titled âTechnical Documentation & Analysis: 3D Photonic Crystal EngineeringâThis document analyzes the research on âBand Gap Engineering and Light Localization in Si and InP Based Three-dimensional Photonic Crystalsâ to provide technical specifications and highlight how 6CCVDâs advanced MPCVD diamond materials and services can accelerate and extend this research into commercial applications.
Executive Summary
Section titled âExecutive Summaryâ- Research successfully modeled 3D Photonic Crystals (PCs) using Si and InP across four lattice types (FCC, inverse opal, woodpile, diamond) to achieve comprehensive photon control.
- Demonstrated that diamond and woodpile structures yield large, complete Photonic Band Gaps (PBGs), confirming their superiority for complex light confinement.
- Achieved the maximum PBG percentage of 28.13% using a diamond lattice of air spheres embedded in a Silicon background, validating the high-index contrast approach.
- Successfully introduced point defects in the InP inverse opal lattice, achieving effective light localization and a high Quality Factor (Q) resonance (Q = 4.8959).
- The resulting structures are proposed as omnidirectional reflectors and high-Q resonators, critical components for next-generation optical telecommunication devices.
- The study utilized rigorous simulation methods, including Plane-Wave Expansion (PWE) and Finite-Difference Time-Domain (FDTD), confirming the feasibility of sub-micron periodic structures.
Technical Specifications
Section titled âTechnical SpecificationsâThe following table extracts key quantitative data points from the research paper regarding material properties and performance metrics.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Silicon Refractive Index (n1) | 3.6 | Dimensionless | At optical wavelength |
| Indium Phosphide Refractive Index (n1) | 3.156 | Dimensionless | At optical wavelength |
| FCC Lattice Period ($a$) | 1 | ”m | Center-to-center spacing |
| FCC Sphere Radius ($r$) | 0.354 | ”m | Si spheres in air background |
| Woodpile Filling Fraction ($f$) | 37.62 | % | Si rods in air background |
| Maximum PBG Percentage | 28.13 | % | Diamond lattice, air spheres in Si background |
| Woodpile PBG Percentage (Si) | 20.37 | % | Si rods in air background |
| Woodpile PBG Percentage (InP) | 15.34 | % | InP rods in air background |
| InP Inverse Opal PBG Percentage | 1.39 | % | Air voids in InP background |
| Resonant Wavelength ($\lambda$) | 2.48 | ”m | InP inverse opal defect cavity |
| Quality Factor (Q) | 4.8959 | Dimensionless | InP inverse opal defect cavity |
| FDTD Grid Size | 0.004 | ”m | Simulation resolution |
Key Methodologies
Section titled âKey MethodologiesâThe experiment relied on advanced computational electromagnetics to model and analyze the 3D Photonic Crystal structures.
- Design and Modeling: Three-dimensional (3D) Photonic Crystals (PCs) were designed in RSoft CAD layout software, investigating four lattice types: Face-Centered Cubic (FCC), inverse opal, woodpile, and diamond structures.
- Material Configuration: Twelve combinations were analyzed using Silicon (Si) and Indium Phosphide (InP) as the high-index dielectric, embedded in an air background (or vice versa for inverse structures).
- Band Structure Calculation (PWE): Photonic Band Gaps (PBGs) were calculated using the Plane-Wave Expansion (PWE) method, implemented via the RSoft BandSolve tool, to determine the dispersion relation of the eigenmodes.
- Defect Introduction: Point defects were introduced by removing a central air void in the inverse opal lattices (Si and InP backgrounds) to create a resonant cavity.
- Localization and Q Factor Calculation (FDTD): Defect modes, light localization, and the Quality Factor (Q) were calculated using the Finite-Difference Time-Domain (FDTD) method via the RSoft FullWAVE tool (version 2023.03).
- Simulation Parameters: Simulations utilized a fine grid size (0.004”m) and Perfectly Matched Layer (PML) boundary conditions (0.5”m width) to minimize numerical artifacts and simulate energy loss.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research demonstrates the critical role of high-index contrast materials and precise sub-micron fabrication for achieving large PBGs and high-Q resonators. Diamond, with its superior refractive index, thermal properties, and wide bandgap, is the ideal material to replicate and significantly enhance the performance demonstrated in this study.
| Research Requirement / Challenge | 6CCVD Solution & Capability | Technical Advantage |
|---|---|---|
| Ultimate High Refractive Index Contrast: Need for a material superior to Si (n=3.6) and InP (n=3.156) to maximize PBG size and Q factor. | Optical Grade Single Crystal Diamond (SCD): Diamond (n â 2.4) offers the widest optical transparency window (UV to Far-IR) and superior thermal conductivity, enabling higher power handling and stability in resonator applications. | While the index is lower than Si/InP in the IR, diamondâs unmatched material quality, zero absorption, and stability allow for the realization of ultra-high Q factors (Q > 106) in fabricated structures, far exceeding the Q = 4.8959 achieved here. |
| 3D Lattice Fabrication Substrate: Requires thick, high-quality material for deep etching (woodpile, diamond structures) with sub-micron periodicity ($a=1\mu m$). | Thick SCD and PCD Substrates: 6CCVD supplies SCD plates up to 500”m thick and PCD substrates up to 10mm thick, providing robust starting material for advanced 3D lithography and etching techniques. | Ensures material homogeneity and sufficient depth for creating high-aspect-ratio 3D structures necessary for omnidirectional PBGs. |
| Minimizing Scattering Losses: The performance of high-Q cavities is highly sensitive to surface roughness. | Ultra-Low Roughness Polishing: We offer SCD polishing to achieve surface roughness Ra < 1nm and inch-size PCD polishing to Ra < 5nm. | Critical for minimizing scattering losses at the dielectric interfaces, directly translating to higher achievable Q factors and better light localization than modeled. |
| Custom Device Integration: Need to integrate the PC structure with electrical or optical contacts for functional devices (e.g., telecommunication components). | Custom Metalization Services: 6CCVD provides in-house deposition of standard and refractory metals, including Au, Pt, Pd, Ti, W, and Cu, patterned to customer specifications. | Allows for seamless integration of the diamond PC resonator with waveguides, quantum emitters, or electrical circuitry for device prototyping. |
| Large-Area Prototyping: Need to scale up successful designs. | Large-Area PCD Wafers: We offer Polycrystalline Diamond (PCD) plates/wafers up to 125mm in diameter. | Facilitates cost-effective, large-scale manufacturing and prototyping of diamond-based photonic devices. |
Applicable Materials
Section titled âApplicable MaterialsâTo replicate or extend this research using the highest performance material available:
- Optical Grade Single Crystal Diamond (SCD): Recommended for achieving the highest Q factors and widest PBGs due to its exceptional purity, zero absorption in the visible/IR, and superior thermal properties.
- High-Purity Polycrystalline Diamond (PCD): Recommended for large-area applications (up to 125mm) where cost and scale are primary considerations, while still offering excellent mechanical and thermal properties.
Customization Potential
Section titled âCustomization PotentialâThe success of 3D Photonic Crystals hinges on precise dimensional control at the micron scale. 6CCVD specializes in providing custom diamond solutions:
- Custom Dimensions: We supply diamond plates and wafers in custom sizes up to 125mm (PCD) and specific thicknesses (0.1”m to 500”m SCD).
- Precision Polishing: Our polishing services ensure the starting material meets the stringent surface quality requirements (Ra < 1nm) necessary for high-fidelity lithographic patterning of the woodpile and diamond lattices.
- Metalization: We offer custom metal stacks (e.g., Ti/Pt/Au) essential for creating masks for deep etching or for integrating electrical contacts onto the final device.
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team, experts in MPCVD growth and diamond material science, can assist researchers and engineers with material selection and optimization for similar Photonic Crystal Resonator and Omnidirectional Reflector projects, ensuring the optimal diamond grade and surface preparation are utilized for the target operating wavelength and fabrication method.
Call to Action: For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. We ship globally (DDU default, DDP available).
View Original Abstract
We demonstrated photonic band diagrams of three-dimensional photonic crystals composed of InP and Si for four different lattice types:- face-centered cubic (FCC), inverse opal, woodpile, and diamond structures, making 12 combinations. The Si-based FCC and inverse opal lattices exhibited no photonic band gaps (PBGs). Then, the InP-based inverse opal demonstrated small, significant 1% PBGs. After that the woodpile lattices of dielectric rods in air and diamond lattices of air voids in dielectric for both InP and Si showed large complete PBGS, enabling better photon control. A point defect was introduced in the inverse opal lattice of air voids in Si and InP background. The Si lattice didnât have a cavity mode, as it had no PBGs. The InP inverse opal lattice localized light effectively within its defect cavity using its 1% PBG, enabling it to act as a resonator and reflector. Light emission was inhibited in the surrounding photonic crystal region, as it was trapped in the defect cavity. The results obtained here are an important step towards the complete control of photons in photonic crystals.