Ultra-narrow band metasurface absorber

The invention discloses an ultra-narrow band metasurface absorber, and relates to the technical field of nanoscale metasurface absorbers. The ultra-narrow band metasurface absorber is composed of a plurality of same cell unit arrays, and each cell unit is composed of a substrate layer, a dielectric layer, a bottom layer circular ring, a middle layer dielectric circular ring, a top layer circular ring, a bottom layer cuboid, a middle layer dielectric cuboid and a top layer cuboid. The dielectric layer is tightly attached to the upper portion of the substrate layer. The dielectric layer is provided with a structure composed of a bottom layer circular ring and a bottom layer cuboid. The bottom-layer circular ring is sequentially covered with a middle-layer medium circular ring and a top-layer circular ring; the bottom-layer cuboid is sequentially covered with a middle-layer medium cuboid and a top-layer cuboid; the ultra-narrow-band metasurface absorber is simple in structure, convenient to process under the con