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arXiv · 1708.00004

Perfect spin filter by periodic drive of a ferromagnetic quantum barrier

Daniel Thuberg·Enrique Munoz·Sebastian Eggert·Sebastian A. Reyes
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Abstract

We consider the problem of particle tunneling through a periodically driven ferromagnetic quantum barrier connected to two leads. The barrier is modeled by an impurity site representing a ferromagnetic layer or quantum dot in a tight-binding Hamiltonian with a local magnetic field and an AC-driven potential, which is solved using the Floquet formalism. The repulsive interactions in the quantum barrier are also taken into account. Our results show that the time-periodic potential causes sharp resonances of perfect transmission and reflection, which can be tuned by the frequency, the driving strength, and the magnetic field. We demonstrate that a device based on this configuration could act as a highly-tunable spin valve for spintronic applications.

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Daniel Thuberg, Enrique Munoz, Sebastian Eggert, Sebastian A. Reyes. 2017-07-31. Perfect spin filter by periodic drive of a ferromagnetic quantum barrier. https://doi.org/10.1103/physrevlett.119.267701

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