Description: Photodetectors and focal plane arrays (FPAs) covering the middle-wave and longwave infrared (MWIR/LWIR) are of great importance in numerous NASA applications, including earth remote sensing for carbon-based trace gases, Lidar mapping for earth resource locating, and environment and atmosphere monitoring. Existing MWIR/LWIR photodetectors have a low operating temperature of below 77K. The requirement for cryogenic cooling systems adds cost, weight and reliability issues, making it unsuitable for satellite remote sensing applications. This STTR project aims to develop a new plasmonic photonic antenna coupled MWIR/LWIR photodetector and FPA with significantly enhanced performance and a high operating temperature. In Phase I, we developed a preliminary plasmonic photonic antenna enhanced MWIR/LWIR photodetector and demonstrated significant enhancement in photodetectivity and operating temperature. Antenna directivity is also tested and agrees with the simulation. The phase I results not only demonstrated the feasibility of achieving high performance MWIR/LWIR photodetector using the proposed innovation, but also show its promising potentials for high operating temperature FPA development. Motivated by the successful feasibility demonstration and the promising potentials, in this STTR Phase II project, we will develop a prototype of the plasmonic photonic antenna enhanced MWIR/LWIR FPA with a high operating temperature and demonstrate its earth remote sensing capability.

Benefits: The proposed plasmonic photonic antenna enhanced MWIR/LWIR photodetector and FPA technology enables ultra-compact high performance MWIR/LWIR sensing with high photodetectivity and a high operating temperature. This technology avoids the bulky and heavy cryogenic cooling system and enables ultra-compact carbon-based trace gases (CH4, CO2, and CO) sensing with substantially reduced device size, weight and power consumption and improved system reliability for small satellite applications. It forms a key building block in IR cameras for numerous NASA's earth remote applications, including space telescope and high-sensitive space object imaging, high definition acquisition of radiation characteristics of Earth and its environments, monitoring of atmospheric variables such as temperature, winds, and trace constituents for understanding and predicting the earth's climate and potential hazards as well as topographical profiling of Earth for mineral identification and vegetation mapping.

The high-performance ultra-compact MWIR/LWIR detector technology is particularly useful for many portable and standalone military and homeland security sensing and imaging applications such as night vision, missile early launch detection and remote chemical sensing and detection for biological/chemical warfare. Commercial markets include leak detection, chemical process control, remote chemical sensing for atmospheric pollution and drug monitoring, IR spectroscopy, and medical diagnoses. The technology developed herein would considerably accelerate the commercialization of IR camera technologies to meet the potential needs of the huge defense and commercial market.