Extraordinary magneto-optical Kerr effect via MoS2 monolayer in Au/Py/MoS2 plasmonic cavity

Abstract

We demonstrate a multilayer magnetoplasmonic structure fabricated from MoS₂ monolayer to significantly increase the magneto-optical Kerr effect (MOKE). The structure is made from glass/Au/Py/MoS₂ × n (where n is the number of MoS₂ monolayers), and the MOKE enhancements are based on the surface plasmon resonance and the extraordinary light absorbing mechanism of the MoS₂ monolayers. The transverse MOKE (TMOKE) is about 18 times larger than that of Au/Py, suggesting the important role of the MoS₂ top layer. Moreover, the calculated Q-factor of the TMOKE signal is found to be about 623, indicating the presence of a sharp cavity resonance that dramatically influences the surface plasmon excitation. Our results convey a new pathway to the design of advanced magneto-optical devices for sensors, recording, etc.