SBIR Phase I: Development of New Time and Spatially-Resolved, Near-Infrared Photoluminescence Techniques Detecting Trapped Charge in Inorganic Sediments for Geochronology Dating

This Small Business Innovation Research Phase I project will develop a rapid, Pulsed Near-Infrared Photoluminescence (P-NIR-PL) and Stimulated Luminescence (SL) technique with micron spatial resolution, as a state-of-the art photoluminescence dating method for inorganic sediments, with substantially improved precision, accuracy, and turn-around time for sample processing. Picosecond-NIR-PL is a next-generation analytical platform for inorganic sediments. The team seeks to capture geochronological data from ~1 to 200,000 years prior. The approach addresses challenges with sample processing through the rapid detection of overlapping PL signals that will be deconvoluted and correlated to age. If successful, this project will provide new capabilities to geologists and archaeologists working on new geochronological methods for dating volcanic soils, charred materials, and sand/rock materials from future extraterrestrial sites. A sizable niche market and strong commercialization opportunity exists if optical dating measurements can be performed rapidly and non-destructively, repeatedly with differentiation on the sub single-grain level, and reliably with minimal sample pre-treatment. The intellectual merit of this project focuses on instrument development to address the immediate demand for an accurate tool for differentiation of quartz and feldspar detection in sediments using an advanced spatial and time-resolved microscopy method with an attached dosing/dating capability for geochronological dating. Separation of PL and SL decays that are previously unexplained will establish a novel geochronological method achieved by expanding the detection into the near-infrared. A picosecond pulsed laser source with picosecond-to-second resolution in kinetic decay will be combined with high spatial resolution to cover a wide range of excitation/emission profiles that uniquely shorten the time required for a single measurement, from 13 hours to 20 minutes. Specifically, the combined time-resolved and spatially-resolved components create a powerful technique to distinguish molecular and crystalline environments as well as to distinguishing emissions from similar spectra and unique elemental microstructures. The proposed activities may advance engineering and science innovation in pulsed optical/NIR dating methods with a focus on high performance, commercial instrument development for rapid sample screening. Establishment of both the state-of-the-art instrumentation and analytical testing service for optical dating will be performed by a new diversified customer segment with implementation of an online geochronological library. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.