Advanced Low-Cost Solar Tracker for Atmospheric Radiation and Optical Depth Measurements

65614 Most photocathode materials, used in detectors for nuclear physics research, have low detection efficiency, requiring detection systems to acquire data for long periods of time to insure that all of the needed information is acquired for a given event. This problem is particularly acute when several photocathode based detectors must act in concert to verify that an event has occurred. This project will develop a new class of high efficiency photocathode ¿metamaterials¿ based on nanowire arrays. These materials can be tailored to a particular band of the spectrum for near unity absorption of incoming radiation, thereby providing a sharp increase inefficiency . In Phase I, simple nanowire photocathodes will be constructed and tested using gold and cesium-gold nanowires. The quantum efficiencies of the nanowire photocathodes will be compared to thin film versions made of the same materials to determine the impact of the nanowire structure on efficiency Commercial Applications And Other Benefits as described by awardee: High efficiency photocathodes should have application in medical imaging equipment to reduce the dose of radiation received by the patient. These materials can also make photomultiplier tubes a viable alternative to PIN and avalanche photodiodes for optical telecommunications receivers.