Metamaterial allows novel nanophotonic applications such as negative permeability, negative refractive index, and near-zero index. In particular, all-dielectric metamaterials recently create new opportunities for manipulating electromagnetic fields, taking full advantage of low-loss, bandwidth enhancement, and isotropic responses. Here a silicon dielectric metamaterial is reported in near-infrared region, exhibiting extraordinarily figure-of-merit, defined by sensitivity (resonance shift/refractive index change) over full width at half maximum, from magnetic resonance shift depending on index changes of surrounding medium. This silicon dielectric metamaterial comprises subwavelength nanohole arrays in a square lattice on an ultrathin amorphous silicon membrane. The ultrathin silicon nanohole membrane is fabricated on a glass wafer by using e-beam lithography, silicon reactive ion etching, and hydrogen fluoride wet etching. This all-dielectric metamaterial successfully demonstrates exceptional figure-of-merit of 29, which is 7.6 times higher than those values of conventional metamaterials. This novel metamaterial enables not only the label-free detection of chemical and biological molecules with different mass concentrations but also the in situ reaction monitoring of biochemical molecules.
Bibliographical noteFunding Information:
S.-G.P. and Y.L. contributed equally to this work. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science, ICT & Future Planning (No. 2015036205, No. 201601306), a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI) funded by of Ministry of Health & Welfare (HI13C2181), the Center for Integrated Smart Sensors funded by the Ministry of Science, ICT & Future Planning as Global Frontier Project (CISS-2011-0031866).
© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
- high sensitivity
- label-free sensing
- refractive index changes
- silicon metamaterials
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics