Spin transfer torque switching of magnetic tunnel junctions using a conductive atomic force microscope

  title={Spin transfer torque switching of magnetic tunnel junctions using a conductive atomic force microscope},
  author={Eric R. Evarts and Limin Cao and David S. Ricketts and Nicholas D. Rizzo and James A. Bain and Sara A. Majetich},
  journal={Applied Physics Letters},
We show that a nonmagnetic conductive atomic force microscopy probe can be used to read and write magnetic bits using current passed between the tip and bit. The bits were patterned using electron beam lithography from a magnetic tunnel junction (MTJ) film with in-plane shape anisotropy using an MgO tunnel barrier. Probes were made having a thick Pt coating and could deliver up to several milliamps, so that MTJ structures were easily switched repeatedly using the spin transfer torque effect. 

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