Extra-narrowband metallic filters with an ultrathin single-layer metallic grating

Wang Ran^{1, 2}, Gong Qi-Huang^{1, 3, 4}, Chen Jian-Jun^{1, 3, 4, †}

(a) SEM image of one gold grating with the period of P = 400 nm. (b) Zoomed-in view of the sample. Experimental transmission spectra of the samples with (c) P = 400 nm, (d) P = 450 nm, and (e) P = 500 nm.