Effect of an Optical Negative Index Thin Film on Optical Bistability
  We investigate nonlinear transmission in a layered structure consisting of a slab of positive index material (PIM) with Kerr-type nonlinearity and a sub-wavelength layer of linear negative index material (NIM) sandwiched between semi-infinite linear dielectrics. We find that a thin layer of NIM leads to significant changes in the hysteresis width when the nonlinear slab is illuminated at an angle near that of total internal reflection. Unidirectional diode-like transmission with enhanced operational range is demonstrated. These results may be useful for NIMs characterization and for designing novel NIMs based devices. 
N. M. Litchinitser, I. R. Gabitov, A. I. Maimistov, and V. M. Shalaev