Large Magnetoresistance at Room Temperature in Ferromagnet/Topological   Insulator Contacts
  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. 
Sarmita Majumder, Samaresh Guchhait, Rik Dey, Leonard Franklin   Register, and Sanjay K. Banerjee
cond-mat.mes-hall