Efficient excitation of surface plasmon polaritons(SPPs)remains one of the most challenging issues in areas of plasmonics related to information communication technologies.In particular,combining high SPP excitation e...Efficient excitation of surface plasmon polaritons(SPPs)remains one of the most challenging issues in areas of plasmonics related to information communication technologies.In particular,combining high SPP excitation efficiency and acceptance of any polarization of incident light appeared to be impossible to attain due to the polarized nature of SPPs.Here we demonstrate plasmonic couplers that represent arrays of gap SPP resonators producing upon reflection two orthogonal phase gradients in respective linear polarizations of incident radiation.These couplers are thereby capable of efficiently converting incident radiation with arbitrary polarization into SPPs that propagate in orthogonal directions dictated by the phase gradients.Fabricated couplers operate at telecom wavelengths and feature the coupling efficiency of,25%for either of two linear polarizations of incident radiation and directivity of SPP excitation exceeding 100.We further demonstrate that an individual wavelength-sized unit cell,representing a meta-scatterer,can also be used for efficient and polarization sensitive SPP excitation in compact plasmonics circuits.展开更多
基金The authors would like to acknowledge the financial support from the Danish Council for Independent Research(the FTP project ANAP,contract no.09-072949,and the FNU project,contract no.12-124690).
文摘Efficient excitation of surface plasmon polaritons(SPPs)remains one of the most challenging issues in areas of plasmonics related to information communication technologies.In particular,combining high SPP excitation efficiency and acceptance of any polarization of incident light appeared to be impossible to attain due to the polarized nature of SPPs.Here we demonstrate plasmonic couplers that represent arrays of gap SPP resonators producing upon reflection two orthogonal phase gradients in respective linear polarizations of incident radiation.These couplers are thereby capable of efficiently converting incident radiation with arbitrary polarization into SPPs that propagate in orthogonal directions dictated by the phase gradients.Fabricated couplers operate at telecom wavelengths and feature the coupling efficiency of,25%for either of two linear polarizations of incident radiation and directivity of SPP excitation exceeding 100.We further demonstrate that an individual wavelength-sized unit cell,representing a meta-scatterer,can also be used for efficient and polarization sensitive SPP excitation in compact plasmonics circuits.
