TY - JOUR T1 - Metamaterials with negative permeability and negative refractive index: experiments and simulations A1 - Ozbay, E. A1 - Guven, K. A1 - Aydin, K. JA - J of Optics A - Pure and Applied Optics Y1 - 2007 VL - 9 SP - 301 EP - 307 ER -