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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
UNCLASSIFIED/ (FOR OFFICII Is WEE IHILY Applications to Circuits and Waveguide Miniaturization: Slowing Down and Manipulating Electromagnetic Pulses (EMP) Using Advanced Metamaterials Given the space constraints of an advanced aerospace platform and the amount of the useful payload that has to be carried, it is very important that every optical and microwave component be as small as possible. Because of the very large speed of light, there is a natural limit to how small such components can be made. Any structure capable of processing EMPs (be those optical, THz, or microwave) of temporal duration r must be at least L = cT long. For example, a 1 ns microwave pulse can be manipulated inside a device that is at least 1 ft long. Pulse manipulation can be understood very broadly by pulse compression, frequency shifting, harmonics generation, or other. For aerospace communications systems, it may be very desirable to have the ability to manipulate the format of EMPs, (that is, to change their frequency, duration, and repetition rate). Slowing down or even stopping the EMP can circumvent the length requirement if the group velocity is reduced to v~ - \. ,.,' ·~ ' .:· ·-- ~ ........ ~: .__. ~ . .... ~ ·- -~> Y_~o. The emerging pulse is compressed to 'Fi = Tvg 0 / vg,. (Reference 29) An example of the pulse slowing down and subsequent manipulation is first discussed in Reference 29 in the somewhat esoteric context of magnetized plasma. Pulse duration, frequency, and (for multiple pulses) repetition rate can be controlled by storing (or slowing down) electromagnetic waves and subsequently changing the system's parameters. The essence of the compact pulse manipulator is shown in Figure 14. The pulse is slowed down ins[de the compact plasma device and manipulated by changing the magnitude of the magnetic field. The advantage of slowing the pulses down is three-fold. First, the device can .be made smaller, resulting in size savings. Second, the temporal scale on which the system has to be manipulated is lengthened because the pulse is moving slowly. Finally, the potentially large ratio between vg 1 >> v~ 11 results in the more dramatic dynamic range of possible pulse compression ratios. Plasma-based 16 UNCLASSIFIEDf/P91l OPrteIML 09c OHLi
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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.