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to within 1% for power levels up to ten Watts. The detector size was 50 mm in diameter and its collecting solid angle is 1.6-1.7. The area of the sample was 10 square millimeters +/- 0.75 square millimeters. Finally, emission spectra are measured using a standard Fourier Transform Infrared Spectrometer on a range of samples and sample sizes. Fig. 1 SEM Micrograph of a metallic Fig. 2 Emission from a structure with photonic crystal. minimum feature size of 0.8 microns. In Fig. 2, the measured emission spectra are shown for a resistively heated sample emitting at —4 p.m. When we measure the actual power density of emission in the range of wavelengths between 3.5 and 4.5 gm. we find that the power density exceeds the value obtained from Planck's law by almost an order of magnitude. We have obtained the same result for thermally heated samples and for samples with emission peaks ranging from 1.5 gm to 6 gm. The emission peak positions are found to scale with the pitch of the lattice. The peak emission is linearly shifted to longer wavelengths for a larger lattice constant. As yet, there is no satisfactory explanation for this experimentally observed deviation from the Planck Radiation Law and its corollaries. Nonetheless, we point out that there exist sufficient differences between blackbody and tungsten photonic-crystal emitters. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL 85000.
DOI link for to within 1% for power levels up to ten Watts. The detector size was 50 mm in diameter and its collecting solid angle is 1.6-1.7. The area of the sample was 10 square millimeters +/- 0.75 square millimeters. Finally, emission spectra are measured using a standard Fourier Transform Infrared Spectrometer on a range of samples and sample sizes. Fig. 1 SEM Micrograph of a metallic Fig. 2 Emission from a structure with photonic crystal. minimum feature size of 0.8 microns. In Fig. 2, the measured emission spectra are shown for a resistively heated sample emitting at —4 p.m. When we measure the actual power density of emission in the range of wavelengths between 3.5 and 4.5 gm. we find that the power density exceeds the value obtained from Planck's law by almost an order of magnitude. We have obtained the same result for thermally heated samples and for samples with emission peaks ranging from 1.5 gm to 6 gm. The emission peak positions are found to scale with the pitch of the lattice. The peak emission is linearly shifted to longer wavelengths for a larger lattice constant. As yet, there is no satisfactory explanation for this experimentally observed deviation from the Planck Radiation Law and its corollaries. Nonetheless, we point out that there exist sufficient differences between blackbody and tungsten photonic-crystal emitters. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL 85000.
to within 1% for power levels up to ten Watts. The detector size was 50 mm in diameter and its collecting solid angle is 1.6-1.7. The area of the sample was 10 square millimeters +/- 0.75 square millimeters. Finally, emission spectra are measured using a standard Fourier Transform Infrared Spectrometer on a range of samples and sample sizes. Fig. 1 SEM Micrograph of a metallic Fig. 2 Emission from a structure with photonic crystal. minimum feature size of 0.8 microns. In Fig. 2, the measured emission spectra are shown for a resistively heated sample emitting at —4 p.m. When we measure the actual power density of emission in the range of wavelengths between 3.5 and 4.5 gm. we find that the power density exceeds the value obtained from Planck's law by almost an order of magnitude. We have obtained the same result for thermally heated samples and for samples with emission peaks ranging from 1.5 gm to 6 gm. The emission peak positions are found to scale with the pitch of the lattice. The peak emission is linearly shifted to longer wavelengths for a larger lattice constant. As yet, there is no satisfactory explanation for this experimentally observed deviation from the Planck Radiation Law and its corollaries. Nonetheless, we point out that there exist sufficient differences between blackbody and tungsten photonic-crystal emitters. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL 85000.
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ABSTRACT