Comment on 'Triple-band perfect metamaterial absorption, based on single cut-wire bar' [Appl. Phys. Lett. 106, 071105 (2015)]

摘要

In a recent letter, Yoo et al. reported a triple-band metamaterial absorber, made of one layer of a grounded rectangular metallic patch array, and claimed that their structure had perfect wave-attenuation performance at various incident polarizations. In this comment, we demonstrate that the apparent "strong absorption" at the polarizations misaligned with the edges of metallic patches was actually caused partially by cross-polarization reflection, which was clearly neglected by the original authors. Thus, at these polarizations, the true absorption was not as perfect as they claimed.