title: Nonlinear absorption due to linear loss and magnetic permeability in metamaterials.
abstract: We predict theoretically that linear magnetic permeability induces nonlinear absorption (NA) of an electric field in lossy metamaterials (MMs) with Kerr-type nonlinear polarization even when the imaginary part of the nonlinear polarization is absent. The nonlinear magnetic susceptibility, if it exists and although it may be real, enhances or reduces the NA of the electric field, depending on the relative values of the electric and magnetic losses. In particular, it is shown that the NA effect can be tuned by the figure of merit (FOM) of the MM: generally, MMs with a better FOM have a weaker NA effect. Moreover, the nonlinear coefficient can also be enhanced greatly due to the combined effect of the linear losses and the nonlinear magnetization of MMs. The control of the tunable NA and nonlinear coefficients by the structural parameters of MMs is also discussed.
authors.affiliation: Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education, College of Information Science and Engineering, Hunan University, Changsha 410082, China. xiangyuanjiang@126.com
authors.forename: Yuanjiang
authors.initials: Y
authors.lastname: Xiang
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Dai
authors.forename: Shuangchun
authors.initials: S
authors.lastname: Wen
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
mesh_terms: D003198:Computer Simulation; D004553:Electric Conductivity; D008280:Magnetics; D008420:Manufactured Materials; D008962:Models, Theoretical; D017711:Nonlinear Dynamics; D010539:Permeability