Spin and valley polarization of an MoS2 zigzag nanoribbon with a magnetic barrier via Fano resonance

초록

For monolayer MoS2, a magnetic field causes the degeneracy of the K and K′ valleys to be lifted, owing to the valley Zeeman effect. Thus, in a monolayer MoS2 nanoribbon system with a magnetic barrier, electrons in these valleys exhibit different conductance behaviors when passing through the barrier. One valley shows a strong dip in conductance caused by Fano resonance, i.e., quantum interference between continuum states and Landau levels in the magnetic barrier. This dip can be modulated by changing the strength and length of the magnetic barrier. By calculating the asymmetric conductance for the K and K′ valleys as a function of incident energy with various values of the physical parameters, optimized conditions for spin and valley polarization can be found. The results presented here provide useful information to enable implementation of spin- and valley-polarized currents in future devices. © 2022 authors. Published by the American Physical Society.