Ultrafast and low-power all-optical switch based on asymmetry electromagnetically induced transparency in MIM waveguide containing Kerr material

We have proposed the analog of electromagnetically induced transparency (EIT) in a metal-insulator-metal (MIM) plasmonic waveguide side coupled with two stub resonators containing Kerr material. The mechanism of the EIT-like transmission sp ectra in our structure is theoretically analyzed and numerically investigated by using the Finite-Difference Time-Domain (FDTD) method. It is found that the symmetry of the EIT-like spectra can be broken and the asymmetry degree of the EIT-like spectra can be enhanced by increasing the width of the double stub resonators. Taking advantage of the asymmetry EIT phenomenon in the proposed plasmonic system, an ultrafast and low-power all-optical switch with femtosecond-scale feedback time and a required bistable pump light intensity as low as 24.2 MW/cm2 was proposed and numerically investigated. The proposed all-optical switch may find potential important applications in highly integrated optical circuits.