Magneto-optic surface plasmon resonance optimum layers: Simulations for biological relevant refractive index changes

Kerstin Kämpf, Sebastian Kübler, Friedrich Wilhelm Herberg, Arno Ehresmann
2012 Journal of Applied Physics  
The transfer matrix method is used to simulate the magneto-optic surface plasmon resonance (MOSPR) of Au/Co/Au trilayer systems focused on the magneto-optic activity in transverse configuration. The results show a strong thickness dependence of the normalized difference of reflectivity at opposite directions of the magnetization (d-signal) and a strong change of the d-signal with the refractive index n of the biologically active layer. Within a range of the refractive index typically covered by
more » ... ypically covered by a commercial SPR biosensor (n ¼ 1:33À1:40), the magnitude of the d-signal of an Au(10:75 nm)/Co(6 nm)/Au(20:25 nm) trilayer decreases from small to large n by a factor > 63. This finding demonstrates that the enhanced sensitivity of an MOSPR biosensor can be exploited only by defined thicknesses of the metal layers for distinct refractive index regions. V C 2012 American Institute of Physics. [http://dx.
doi:10.1063/1.4742130 fatcat:vmv4glwjx5dlpjeba7jjijgsxe