Programmable phase-change medium-assisted hyperbolic metamaterial as a dual-band nearly perfect absorber
M. Pourmand, P. K. Choudhury
Abstract
A programmable phase-change medium-based hyperbolic metamaterial with tunable perfect absorption in the visible and near-infrared regimes was investigated. The stochastic particle swarm optimization was used in the design process, followed by the transfer matrix method to further investigate the angle-invariant and polarization-insensitive spectral properties. Absorption <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>></mml:mo> </mml:mrow> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>90</mml:mn> </mml:mrow> </mml:mrow> <mml:mi mathvariant="normal">%</mml:mi> </mml:math> in the visible regime along with nearly perfect absorption ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mo>></mml:mo> </mml:mrow> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>99</mml:mn> </mml:mrow> </mml:mrow> <mml:mi mathvariant="normal">%</mml:mi> </mml:math> ) with 80 nm full width at half-maximum was achieved, which can be tuned in a range of 1.31–1.57 µm.