Giant Tunnel Magnetoresistance with a Single Magnetic Phase-Transition Electrode

A magnetic tunnel junction with a $s\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}g\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}e$ magnetic electrode, rather than the usual two, would be interesting for magnetoresistance (MR) -based devices in spintronics, but a low MR ratio remains as one of the main obstacles. This study uses first-principles calculations to investigate MPT-TMR, the change in tunneling magnetoresistance due to a magnetic phase transition of the electrode, in an \ensuremath{\alpha}'-FeRh/MgO/Cu tunnel junction. In this case the MPT-TMR ratio is predicted to be high---up to hundreds of percents. This plus structural simplicity, tunable spin injection with nearly complete spin polarization, and electric-field-driven switching make this system quite promising for applications.