Description: Agiltron proposes to develop an extremely compact and high sensitivity uncooled near- and mid-infrared (NMIR) spectrometer engine for planetary compositional analysis and mapping. In this program, we will produce lead salt-based IR detector materials with single crystalline-like oriented thin film structures which will increase the majority charge carrier mobility by two orders of magnitude. Exceptionally high charge carrier mobility will significantly improve photosensitivity and greatly reduce noise of the IR detectors and detector arrays. We will produce this unique thin film structure by employing so called "nano-graphoepitaxy", in which lead salt thin films are deposited on nanoengineered substrates, then followed by sensitizing them in controlled process conditions. Micro-grooved substrates will further enhance photon absorption efficiency via the ray optics. Furthermore, we will design and develop an extremely compact and high spectral resolution spectrometer engine by employing an aperiodic nanostructure-based spectrometer platform. In Phase I, we will design, fabricate and test nanoengineered NMIR detector materials and arrays. We will also conceptually design the aperiodic nanostructure-based spectrometer for NMIR applications. In Phase II, we will produce and evaluate the performance of a prototype uncooled near- and mid-IR spectrometer engine by integrating the high sensitivity detector arrays into the aperiodic nanostructured spectrometer platform.

Benefits: By achieving exceptionally high carrier mobility, the proposed PbS and PbSe detector array will exhibit superior uncooled detectivity and signal to noise ratio (SNR) over the spectral range of 1-5 m. Furthermore, the resulting NMIR spectrometer engine will be compact, reliable, and have high detectivity, high spectral resolution and low power consumption. Therefore, both the NMIR detector array and spectrometer engine to be developed in this program will have immediate applications for NASA's many current and future planetary missions, including in-situ composition analyses of the planetary atmospheres. The compact and high spectral resolution uncooled spectrometer engine will be an invaluable tool to actively investigate planetary atmospheres from both on-ground, such as Mars Rovers, and orbit platforms. The NMIR detector array with superior detectivity and SNR will also be an invaluable tool for both remote sensing and imaging applications from space and orbit platforms.

Industries typically rely on using a small number of high-priced IR spectrometers to handle their process-monitoring needs. Though a single system can be used to monitor several processes simultaneously through multiplexing, it is costly to set up and risky if equipment failure occurs. Compact and inexpensive IR spectrometers can be assembled to operate over the important 1-5 m spectral range by using PbS and PbSe detector arrays. Current PbS and PbSe detector arrays; however, have limitations of relatively low sensitivity and high background noise, partially due to low carrier mobility of 1-5 cm2/V-S. By significantly increasing the carrier mobility, expected to be about 500 cm2/V-S, we can produce mid-IR detector arrays and spectrometers with exceptionally high detectivity and SNR. The compact, affordable NMIR spectrometer to be developed in this program should find many commercial applications in the areas of industry process control and analytical characterization of food, chemicals, and pharmaceuticals.