The DOE Solar Energy Technologies Program FY 2004 Annual Report chronicles the R&D results of the U.S. Department of Energy Solar Energy Technologies Program for Fiscal Year 2004. In particular, the report describes R&D performed by the Program's national laboratories (National Renewable Energy Laboratory, Sandia National Laboratories, Oak Ridge National Laboratory, and Brookhaven National Laboratory) and university and industry partners.

Research done by the Infrared Photonics team at PNNL is focused on developing miniaturized integrated optics for the MWIR and LWIR by exploiting the unique optical and material properties of chalcogenide glass. PNNL has developed thin film deposition capabilities, direct-laser writing techniques, IR photonic device demonstration, holographic optical element design and fabrication, photonic device modeling, and advanced optical metrology - all specific to chalcogenide glass. Chalcogenide infrared photonics provides a pathway to Quantum Cascade Laser (QCL) transmitter miniaturization. QCLs provide a viable infrared laser source for a new class of laser transmitters capable of meeting the performance requirements for a variety of national security sensing applications. The high output power, small size, and superb stability and modulation characteristics of QCLs make them amenable for integration as transmitters into ultra-sensitive, ultra-selective point sampling and remote short-range chemical sensors that are particularly useful for nuclear nonproliferation missions.

The principal goal of Pacific Northwest National Laboratory's (PNNL's) Infrared Technology for Advanced Sensors Project is to explore and develop the science and technology behind point and stand off infrared (IR) spectroscopic chemical sensors that are needed for detecting weapons proliferation activity. The primary use of the technology is to detect the chemical signatures associated with the production or use of chemical, biological, or nuclear weapons. In FY04 PNNL continued the development of a Shortwave Infrared (SWIR) point sensor based on optical Cavity Ringdown Spectroscopy (CRDS). During the year this instrument participated in 3 field tests, including the indoor UF6 release experiment which took place on the Hanford Site in Aug. 2004. The field tests demonstrated the robustness of CRDS as a fieldable technology for sensitive detection of airborne analytes. The instrument was altered from detecting ammonia with a detection limit of {approx} 1 ppmv to detect hydrogen fluoride with a detection limit of {approx} 3 ppbv. The differences in limits of detection between these two chemicals is accounted for by the relative differences in the absorption strength of the two molecules (with HF having a much larger absorption strength than ammonia). In addition to the field tests, the instrument …