Triple band diamond-shaped polarization insensitive plasmonic nano emitter for thermal camouflage and radiative cooling
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2024-05-13 |
| Journal | Optical and Quantum Electronics |
| Authors | Atıf Kerem Ćanlı, Timuçin Emre Tabaru, Veli Tayfun Kılıç |
| Institutions | Sivas Bilim ve Teknoloji Ăniversitesi, Abdullah GĂŒl University |
| Citations | 8 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Triple Band Plasmonic Nano Emitter
Section titled âTechnical Documentation & Analysis: Triple Band Plasmonic Nano EmitterâThis document analyzes the research on a novel Metal-Insulator-Metal (MIM) nano-infrared emitter designed for thermal camouflage and radiative cooling. It highlights the technical achievements and connects the material requirements to 6CCVDâs advanced MPCVD diamond solutions, positioning our products as the ideal platform for replicating and advancing this stealth technology.
Executive Summary
Section titled âExecutive Summaryâ- Core Achievement: Design and simulation of a Diamond-shaped Nano Emitter (DNE) MIM structure (Ag/Si${3}$N${4}$/Ag) achieving polarization-insensitive, triple-band selective infrared absorption.
- High Absorption Performance: The DNE exhibits high absorption (over 90%) across four narrow resonance peaks located simultaneously in the Short-Wave Infrared (SWIR, 2.20-2.99 ”m) and Mid-Wave Infrared (MWIR, 3.99 ”m) windows.
- Radiative Cooling Capability: Achieves exceptional broadband absorption (over 97%) in the Non-Transmissive Infrared Range (NTIR, 5-8 ”m), demonstrating strong radiative cooling characteristics.
- Thermal Camouflage Efficacy: The structure maintains low average emissivity (0.33 in LWIR) and significant signature reduction in MWIR and LWIR, even at temperatures up to 1000 K.
- Physical Mechanism: High absorption is driven by strong field enhancement resulting from the excitation of Surface Plasmon Polaritons (SPPs) at the metal-dielectric interface and Fabry-Perot modes within the Si${3}$N${4}$ layer.
- Fabrication Potential: The design uses CMOS-compatible materials and simple geometry, supporting the feasibility of large-area, cost-effective fabrication, a key requirement for scaling metamaterial arrays.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the optimized DNE structure and performance analysis:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Structure Type | MIM Nano Emitter | N/A | Diamond-shaped Ag grating on Si${3}$N${4}$/Ag substrate |
| SWIR Peak 1 ($\lambda_1$) | 2.20 | ”m | Absorption > 90% |
| SWIR Peak 2 ($\lambda_2$) | 2.54 | ”m | Absorption > 90% |
| SWIR Peak 3 ($\lambda_3$) | 2.99 | ”m | Absorption > 90% |
| MWIR Peak 4 ($\lambda_4$) | 3.99 | ”m | Absorption > 90% |
| NTIR Peak 5 ($\lambda_5$) | 7.4 | ”m | Broadband Absorption > 97% |
| Ag Substrate Height ($H_1$) | 100 | nm | Bottom metal layer thickness |
| Si${3}$N${4}$ Dielectric Height ($H_2$) | 350 | nm | Middle insulator layer thickness |
| Ag Grating Thickness ($t$) | 20 | nm | Top metal layer thickness |
| Grating Side Length ($N$) | 900 | nm | Critical dimension for nanoantenna |
| Periodicity ($P$) | 2090 | nm | Unit cell pitch (2.09 ”m) |
| Average Emissivity (LWIR) | 0.33 | N/A | Signature reduction performance (300 K to 1000 K) |
| Effective Impedance ($Z_{air}$) | 377 | $\Omega$ | Near-zero reflection achieved by impedance matching |
Key Methodologies
Section titled âKey MethodologiesâThe DNE performance was validated through rigorous simulation and analysis:
- Simulation Tool: 3D Finite-Difference Time-Domain (FDTD) method was used to model the electromagnetic response of the nanoantenna structure across the 1-12 ”m wavelength range.
- Boundary Conditions: Periodic boundary conditions were applied in the x and y axes to simulate an infinite array, and a Perfect Match Layer (PML) was used in the z-axis to absorb outgoing waves.
- Optimization Process: Single parameter sweep analysis (grating thickness $t$, side length $N$, periodicity $P$) was performed first, followed by dual parameter sweeps to fine-tune the structure for maximum absorption amplitude and precise resonance peak placement within atmospheric windows.
- Absorption Calculation: Absorption ($A$) was determined using S-parameters, simplified to $A = 1 - R = 1 - |S_{11}|^2$, due to the use of a metal substrate resulting in negligible transmission ($T \approx 0$).
- Effective Impedance Matching: The effective impedance ($Z_{eff}$) was calculated and shown to match the impedance of the surrounding air ($377 \Omega$) at resonance wavelengths, confirming minimal reflection and maximum absorption.
- Physical Mechanism Analysis: E-field and H-field distribution profiles were extracted to confirm the excitation of Surface Plasmon Polaritons (SPPs) at the Ag/Si${3}$N${4}$ interface and Fabry-Perot modes within the Si${3}$N${4}$ dielectric layer, which are responsible for the high absorption rates.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research demonstrates the critical need for ultra-precise material platforms capable of supporting complex nano-patterning, thin-film deposition, and extreme thermal managementâareas where 6CCVDâs MPCVD diamond excels.
| Research Requirement / Challenge | 6CCVD Diamond Solution & Capability | Value Proposition for Replication/Advancement |
|---|---|---|
| Thermal Management Substrate: Need for high-efficiency heat dissipation to maintain performance (crucial for DNE efficiency). | Thermal Grade SCD or PCD: Diamond possesses the highest known thermal conductivity (up to 2000 W/mK). Using diamond as the base substrate dramatically improves heat spreading and stability compared to standard materials like Si or Ag. | Enhanced Efficiency & Robustness: Provides a thermally stable platform for high-power or high-temperature camouflage applications (up to 1000 K, as tested in the paper). |
| High-Fidelity Nano-Patterning: Requires extremely low surface roughness (Ra) for lithography of the 900 nm diamond-shaped grating. | Precision Polished SCD: We offer Single Crystal Diamond (SCD) plates with surface roughness Ra < 1 nm, and inch-size Polycrystalline Diamond (PCD) with Ra < 5 nm. | Superior Patterning Yield: Ensures the structural integrity and optical quality necessary for achieving the precise plasmonic resonances (SPPs and Fabry-Perot modes) demonstrated in the simulations. |
| MIM Structure Metalization: Requires precise deposition of metal layers (Ag, Au, Ti, etc.) for the nanoantenna and substrate. | Custom Metalization Services: 6CCVD provides in-house deposition of critical metals including Au, Pt, Pd, Ti, W, and Cu onto diamond substrates. We support film thicknesses from nanometers (e.g., the 20 nm grating layer) to microns. | Integrated Fabrication: Streamlines the supply chain by providing the high-quality diamond substrate and the necessary metal thin-film layers, ready for subsequent lithography steps. |
| Scalability and Large-Area Arrays: Need for large wafers compatible with CMOS fabrication methods. | Large-Area PCD Wafers: We supply custom Polycrystalline Diamond (PCD) wafers up to 125mm in diameter, enabling the large-scale production of metamaterial arrays required for commercial stealth technology. | Commercial Viability: Provides the necessary dimensions and material quality for transitioning advanced nanoantenna designs from R&D to mass production. |
| Optical Transparency: Need for low-loss material in the SWIR/MWIR/NTIR range (1-12 ”m). | Optical Grade SCD/PCD: Our diamond materials exhibit exceptional transparency across the entire infrared spectrum, making them ideal for integrating active or passive optical components within the camouflage system. | Optimized Infrared Performance: Ensures minimal parasitic absorption losses in the substrate, maximizing the efficiency of the designed plasmonic emitter. |
For custom specifications or material consultation on advanced thermal management, metamaterials, or infrared optical projects, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Abstract This study proposes the design of a novel Metal-Insulator-Metal (MIM) nano-infrared emitter that uses a unique diamond-shaped grating to achieve selective infrared absorption. Diamond-shaped nano emitter (DNE) structure exhibits four narrow resonant peaks within key absorption windows such as short-wave infrared (SWIR) mid-wave infrared (MWIR), alongside with a wide absorption band in the Non-Transmissive Infrared Range (NTIR) for thermal camouflage applications compatible with radiative cooling. Moreover, the proposed DNE is polarization insensitive as it has an in-plane symmetric design. Using the 3D Finite-Difference Time-Domain (FDTD) simulations, we demonstrate the nanoantennaâs superior performance characterized by its high absorption rates and tuned effective impedance matching. As of our knowledge, the findings suggest that this is the first time that a MIM structure achieved multiple narrow resonance peaks, located in SWIR and MWIR simultaneously, with a wide absorption range in NTIR. Represented DNE stands as a significant innovation in the field of stealth technology, providing a tunable, high-efficiency solution for managing and controlling thermal emissions across diverse applications.