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Excitonic Magneto-Optical Kerr Effect in 2D Transition Metal Dichalcogenides Induced by Spin Proximity

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 نشر من قبل Nuno Peres
 تاريخ النشر 2020
  مجال البحث فيزياء
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In this paper we develop the excitonic theory of Kerr rotation angle in a two-dimensional (2D) transition metal dichalcogenide at zero magnetic field. The finite Kerr angle is induced by the interplay between spin-orbit splitting and proximity exchange coupling due to the presence of a ferromagnet. We compare the excitonic effect with the single particle theory approach. We show that the excitonic properties of the 2D material lead to a dramatic change in the frequency dependence of the optical response function. We also find that the excitonic corrections enhance the optical response by a factor of two in the case of MoS2 in proximity to a Cobalt thin film.

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