By Peter Weiss
Lattices of microscopic tungsten rods can act as heat shields, researchers have found. Such structures may dramatically boost the efficiency of incandescent light bulbs and of thermophotovoltaic devices, which convert radiated heat into electricity, says research leader Shawn Yu Lin of the Sandia National Laboratories in Albuquerque, N.M.
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For about 15 years, scientists have been developing orderly microstructures called photonic crystals that block electromagnetic radiation within certain bands of wavelengths (SN: 1/26/02, p. 61: Metallic materials made to order). Expecting to use the crystals for room-temperature applications, such as circuits that would conduct photons instead of electrons, the developers haven’t worried about creating devices that can withstand high temperatures.