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This Defense Intelligence Reference Document from the Defense Intelligence Agency, dated 6 April 2010, reviews electromagnetic and optical metamaterials for aerospace use. It was produced in FY 2009 under the Advanced Aerospace Weapon System Applications (AAWSA) Program. The report covers super-lenses and hyper-lenses for imaging objects smaller than the diffraction limit, slowing light to shrink components, energy-harvesting absorbers, and one-way chiral devices. It concludes that metamaterials matter for aerospace because they allow smaller, lighter components.
“The Advance”11 pages
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Our implementation of the FSL utilizes an IPM whose dielectric permittivity tensor is
anisotropic and contains positive and negative components: 0: 1 > 0,.5i1 col c) with as little decay as possible. That happens because
these sub-diffraction waves are no longer evanescent: kf :::i -k}c11 Is 1 > 0. It is
demonstrated experimentally that there exists a frequency range for which sub-
diffraction waves propagate through the IPM with less attenuation than the radiation-
zone waves (k11 " o.r,:kr •
• ,1·; 11r1J..i ·
··• • ~i';ordtr '"
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• -(: 11r1H .•
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.. ·:··· ....... :
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► ◄ ' ►
10.9 11.0 11.1 11.2 11.3 11.4
Wavelength (um)
Figure 11. First Experimental Demonstration of Propagating Sub-Diffraction Waves in the IPM. (Left):
Experimental setup demonstrating how sub-diffraction waves are launched into the IPM using FIB-fabricated sub-
wavelength grating. Because the periods of the bottom ("launching") and top ("transforming") gratings are
dtfferent, far-field observation of different harmonics of the bottom grating is enabled. (Right): Experimental
results: the first sub-diffraction harmonic of the grating (green line) becomes stronger than the zeroth radiation-
zone harmonic of the grating (blue line) in the region where & . > 0, i,11 < 0.
Once sub-diffraction waves propagate through the 1PM, they can diffract on the image-
releasing grating (see Figure 10) and be radiated out into the far field. A detector array
can be used to collect the signal and reconstruct the image. Unfortunately, different
wave numbers k11 of the object are directed into the same detector and produce an
ambiguity in extracting their respective amplitudes A(k11). This ambiguity is illustrated
by Figure 10: wave numbers kl = M + 2n- / D and k2 = Ak + 41l" ID are directed to the
same far-field detector. Simply put, a single number (intensity of light with the wave
number !!.k < ml c incident on the detector) is insufficient for determining two scattering
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Report, from the dia collection. The PDF is mirrored here; the original link is above. 27 pages are in the text index: search them above, or from the library's search.