Plasmonic-Enhanced Type II Superlattice (T2SL) for High-Performance, High-Temperature LWIR/VLWIR Imaging

We propose to develop and demonstrate high-operating-temperature (HOT) LWIR and VLWIR focal plane arrays (FPAs) based on a plasmonically enhanced Type-II superlattice (T2SL) detector architecture. By integrating a highly doped n++ InAsSb “plasmonic” layer and an optimized grating, our ultra-thin (~0.2 µm) SLS absorber can achieve strong optical absorption without the performance drawbacks of thick conventional T2SLs. This design offers significantly lower dark current, enabling operation at elevated temperatures and reducing bulky cryocooling requirements. During Phase I, we validated the core plasmonic concept at 10.5 µm cutoff, demonstrating both feasibility and high quantum efficiency (QE) potential. In Phase II, we will refine the detector structure, optimize material growth (MBE), and fabricate a 640 × 512 FPA in collaboration with Attollo Engineering, who will provide the advanced DROIC with in-pixel digitization. Our integrated supply chain—spanning Amethyst Research (prime), the University of Oklahoma, Lancaster/IntelliEPI for epitaxial wafers, and Attollo for ROIC hybridization—ensures a complete pathway from wafer growth to camera-level performance validation. This effort will yield the first HOT LWIR/VLWIR FPA for NASA, DoD, and commercial markets, delivering high-sensitivity IR imaging with simplified thermal management and versatile applicability from Earth observation and space exploration to environmental monitoring and defense systems.
Benefits: 1. Earth Observation: Thermal imaging of terrestrial phenomena (e.g., volcanic activity, wildfire monitoring, climate studies) with improved sensitivity at higher sensor temperatures. 2. Planetary Exploration: Enhanced LWIR/VLWIR FPAs for orbiters, landers, and rovers, mapping planetary surfaces or atmospheres where cryocoolers are logistically challenging. 3. Astrophysics & Space Telescopes: Ultra-thin T2SL-based sensors can potentially reduce payload size, weight, and power (SWaP) while capturing faint IR signals from cosmic sources. 4. Space-Based Greenhouse Gas Detection: Reliable IR imaging to track and analyze CO_2, CH_4, and other greenhouse gas distributions, supporting NASA’s climate-monitoring initiatives. By offering a high-quantum-efficiency, HOT-compatible solution, our plasmonic T2SL design aligns with NASA’s technology roadmaps for advanced sensors and instrumentation, reducing the reliance on bulky cooling infrastructure and enabling lighter, more versatile spacecraft and instrument packages. 1. Defense & Security: DoD programs require high-performance LWIR imagers for threat detection, targeting, and surveillance—especially in HOT environments where conventional cooled detectors are impractical or expensive to maintain. 2. Industrial Process Monitoring & Environmental Control: Long-wave IR cameras can detect leaks, thermal inefficiencies, and process anomalies in real-time, improving safety and productivity. 3. Commercial Thermal Imaging: A robust supply of HOT LWIR imagers will reduce total camera costs and open doors to automotive night-vision, perimeter security, and smart home applications. 4. Waste Management & Recycling: IR sorting systems can identify specific plastics or organic materials through characteristic thermal signatures, streamlining recycling and waste reduction. Overall, the plasmonically enhanced T2SL detector stands to disrupt the broader IR imaging market by blending high sensitivity, extended spectral coverage, and substantially reduced cooling needs, translating into new performance benchmarks across aerospace, defense, and commercial sectors.