Low frequency lumped element-based negative index metamaterial

A lumped element-based negative index metamaterial (NIM) was designed, fabricated, and tested for operation at 400 MHz in the ultrahigh frequency (UHF) band. At 400 MHz the measured real part of the index of refraction of this NIM was n(real)=-3.11 with a loss that was less than 1 dB/cm using unit cells whose overall size d was lambda/d similar to 75. The NIM bandwidth was > 10% in the neighborhood of 400 MHz. (C) 2007 American Institute of Physics.