On-Off Switching with Magnetic Field

12/11/2016

The realization of silicon photonic devices is made possible due to the confinement of light in nanometer structures. Another example of tight confinement of the light field are surface plasmons-polaritons which are coupled light-electron plasma waves, propagating at the interface between a dielectric and conducting material. They are extremely sensitive to the dielectric properties of the materials which makes them very interesting also for sensing applications and have given rise to the field of plasmonics. The combination of plasmonics with magneto-optical materials is particularly interesting because it introduces a nanoscale interaction between light felds and magnetisation, hence opening up the possibility of using either one of these fields to control the other. My particular contribution in this area was to derive the influence of magnetization on the light propagation in plasmonic waveguides. I was able to demonstrate how the magnetic field can be used to switch dipole emission on and off and to spatially direct the light out of a plasmonic cavity. This raises the novel possibility of using magnetic fields to control light propagation in nanostructures and using light to sense the magnetic properties in nanoscale domains.