We have fabricated optical absorbers based on heterostructures composed of thick metallic films and truncated all-dielectric photonic crystals. Under the tunneling mechanism, the light can enter the heterostructure without reflection and is greatly absorbed due to the strong local-field enhancement in the metallic film. With the increase in the thickness of the metal, the absorbance will tend to unity. Experiments, in good agreement with the simulations, demonstrate a maximum of absorbance close to 98%. Possible methods to realize a wide-angle or/and wideband absorption are also given.
© 2010 Optical Society of America
Original Manuscript: April 2, 2010
Revised Manuscript: June 16, 2010
Manuscript Accepted: July 13, 2010
Published: August 12, 2010
Gui-qiang Du, Hai-tao Jiang, Zhan-shan Wang, Ya-ping Yang, Zi-li Wang, Hai-qing Lin, and Hong Chen, "Heterostructure-based optical absorbers," J. Opt. Soc. Am. B 27, 1757-1762 (2010)