A wide-band perfect light absorber at mid-wave infrared using   multiplexed metal structures
  We experimentally demonstrate a wide band near perfect light absorber in the mid-wave infrared region using multiplexed plasmonic metal structures. The wide band near perfect light absorber is made of two different size gold metal squares multiplexed on a thin dielectric spacing layer on the top of a thick metal layer in each unit cell. We also fabricate regular non-multiplexed structure perfect light absorbers. The multiplexed structure IR absorber absorbs above 98% incident light over a much wider spectral band than the regular non-multiplexed structure perfect light absorbers in the mid-wave IR region. 
Joshua Hendrickson, Junpeng Guo, Boyang Zhang, Walter Buchwald, and   Richard Soref
physics.optics