All-optical magnetization switching by counterpropagataion or two-frequency pulses using the plasmon-induced inverse Faraday effect in magnetoplasmonic structures

In this Rapid Communication, we study the generation of quasistatic magnetic fields by the plasmon-induced inverse Faraday effect and present analytical and numerical results for the computation of the induced magnetic field distributions in magnetoplasmonic waveguides. We show that the magnetization of a magnetic area can be reversed within sub-picosecond time in nanoconfined magnetoplasmonic waveguides by surface plasmon polaritions (SPP) and the magnetization can be switched back by a SPP propagating into the opposite direction. In addition, we study a magneto-optical dielectric cavity side coupled to a metal-insulator-metal (MIM) waveguide and show that magnetization switching can be implemented in this structure by SPPs generated by two-frequency pulses as well as by counter-propagating SPPs. These phenomena could open up a new energy-efficient ultrafast method for nanoconfined all-optical magnetization switching.