  Metamaterials are patterned metallic structures which permit access to a
novel electromagnetic response, negative index of refraction, impossible to
achieve with naturally occurring materials. Using the Babinet principle, the
complementary split ring resonator (SRR) is etched in a metallic plate to
provide negative \epsilon, with perpendicular direction. Here we propose a new
design, etched in a metallic plate to provide negative magnetic permeability
\mu, with perpendicular direction. The combined electromagnetic response of
this planar metamaterial, where the negative \mu comes from the aperture and
the negative \epsilon from the remainder of the continuous metallic plate,
allows achievement of a double negative index metamaterial (NIM) with only one
metasurface and strong transmission. These designs can be used to fabricate
NIMs at microwave and optical wavelengths and three-dimensional metamaterials.
