Large-area magnetic metamaterials via compact interference lithography

Magnetic metamaterials with magnetic-dipole resonances around 1.2-mu m wavelength are fabricated using an extremely compact and robust version of two- or three-beam interference lithography for 1D and 2D structures, respectively. Our approach employs a single laser beam at 532-nm wavelength impinging onto a suitably shaped dielectric object ( roof-top prism or pyramid) - bringing the complexity of fabricating magnetic metamaterials down to that of evaporating usual dielectric/metallic coatings. The measured optical spectra agree well with theory; the retrieval reveals a negative magnetic permeability. Importantly, the large-scale sample homogeneity is explicitly demonstrated by optical experiments. (c) 2007 Optical Society of America.