Polarization-dependent perfect absorbers/reflectors based on a three-dimensional metamaterial

Conventionally a flat, shiny metal surface can be used as a reflector. Here we show that a microstructured metal surface can be switched from a perfect reflector to a perfect absorber by merely changing the polarization of the incident light. The structure consists of arrays of three-dimensional standing U-shaped resonators (SUSRs), which are fabricated by two-photon polymerization followed by blanket coating of the metal. For the incidence with a specific polarization, light can be perfectly reflected. By changing the polarization of incident light for 90^∘{}, light neither transmits nor reflects. Since the electromagnetic resonance occurs in between the standing arms of a U-shaped resonator, the heat generated in the absorption process is expected to dissipate more easily. The thermal stability of the SUSR absorber has also been investigated.