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arXiv · 1410.2978

Valley- and spin-filter in monolayer MoS$_2$

Leyla Majidi·Moslem Zare·Reza Asgari
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Abstract

We propose a valley- and spin-filter based on a normal/ferromagnetic/normal molybdenum disulfide (MoS$_2$) junction where the polarizations of the valley and the spin can be inverted by reversing the direction of the exchange field in the ferromagnetic region. By using a modified Dirac Hamiltonian and the scattering formalism, we find that the polarizations can be tuned by applying a gate voltage and changing the exchange field in the structure. We further demonstrate that the presence of a topological term ($β$) in the Hamiltonian results in an enhancement or a reduction of the charge conductance depending on the value of the exchange field.

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Leyla Majidi, Moslem Zare, Reza Asgari. 2014-10-11. Valley- and spin-filter in monolayer MoS$_2$. https://doi.org/10.1016/j.ssc.2014.09.008

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