In a paper published in Applied Physics Letters, Larouche et al. present the first quantitative characterization of nonlinear metamaterials. Using an approach based on transfer matrices previously developed in the CMIP, they determine the quadratic nonlinear magnetic susceptibility of a slab of varactor-loaded split ring resonators to be 3.5 m/V. This gigantic value confirms qualitative predictions found in the literature and supports the validity of an analytical model developed by Poutrina et al.
Experimental determination of the quadratic nonlinear magnetic susceptibility of a varactor-loaded split ring resonator metamaterial, Larouche, S., Rose, A., Poutrina, E., Huang, D., and Smith, D. R. , Applied Physics Letters, Jul 5, Volume 97, Number 1, p.011109, (2010).