Large Magnetoresistance at Room Temperature in Ferromagnet/Topological Insulator Contacts

Sarmita Majumder; Samaresh Guchhait; Rik Dey; Leonard Franklin Register; Sanjay K. Banerjee

doi:10.1109/tnano.2016.2572003

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arXiv · 1603.07283

Large Magnetoresistance at Room Temperature in Ferromagnet/Topological Insulator Contacts

Sarmita Majumder·Samaresh Guchhait·Rik Dey·Leonard Franklin Register·Sanjay K. Banerjee

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Abstract

We report magnetoresistance for current flow through iron/topological insulator (Fe/TI) and Fe/evaporated-oxide/TI contacts when a magnetic field is used to initially orient the magnetic alignment of the incorporated ferromagnetic Fe bar, at temperatures ranging from 100 K to room temperature. This magnetoresistance is associated with the relative orientation of the Fe bar magnetization and spin-polarization of electrons moving on the surface of the TI with helical spin-momentum locking. The magnitude of the observed magnetoresistance is relatively large compared to that observed in prior work.

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Sarmita Majumder, Samaresh Guchhait, Rik Dey, Leonard Franklin Register, Sanjay K. Banerjee. 2016-03-23. Large Magnetoresistance at Room Temperature in Ferromagnet/Topological Insulator Contacts. https://doi.org/10.1109/tnano.2016.2572003

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