Perfect impedance-matched left-handed behavior in combined metamaterial N. T. Tung, T. X. Hoai, V. D. Lam, J. W. Park, V. T. Thuy and Y. P. Lee Eur. Phys. J. B, 74 1 (2010) 47-51 Published online: 23 February 2010 DOI: 10.1140/epjb/e2010-00067-8