A Broadband Micro-machined Far-Infrared Absorber

Abstract

The experimental investigation of a broadband far-infrared meta-material absorber is described. The observed absorptance is $>0.95$ from $1-20\mathrm{THz}$ ($300-15\mu \mathrm{m}$) over a temperature range spanning $5-300\mathrm{K}$. The meta-material, realized from an array of tapers $\approx 100\mu \mathrm{m}$ in length, is largely insensitive to the detailed geometry of these elements and is cryogenically compatible with silicon-based micro-machined technologies. The electromagnetic response is in general agreement with a physically motivated transmission line model.

6 pages, 2 figures, published -- Review of Scientific Instruments 87, 054701 (2016)