  In this paper, a plasmonic absorber consisting of a metal-dielectric-metal
stack with a top layer of Sierpinski nanocarpet is theoretically investigated.
Such compact absorber depicts broadband angle-independent behavior over a wide
optical wavelength range ($400-700$ nm) and a broad range of angles of light
incidence ($0-80^{\circ}$). Including several feature sizes, such fractal-like
structure shows widely strong extinction ($85-99$%) response for either
transverse electric or magnetic polarization states under normal incidence.
Underlying mechanisms of absorbance due to excited surface plasmon modes as
well as electric/magnetic dipole resonances are well revealed by investigating
electric field, magnetic field and current distributions. The proposed absorber
opens a path to realize high-performance ultrathin light trapping devices.
