Spin-Torque Switching with the Giant Spin Hall Effect of Tantalum

Liu, Luqiao
Pai, Chi-Feng
Li, Y.
Tseng, H. W.
Ralph, D. C.
Buhrman, R. A.

¹Cornell University, Ithaca, NY 14853, USA. ²Kavli Institute at Cornell, Ithaca, NY 14853, USA.
^*These authors contributed equally to this work.
†To whom correspondence should be addressed. E-mail: [email protected]

Acknowledgments: We acknowledge support from the Army Research Office, Defense Advanced Research Projects Agency, Office of Naval Research, and NSF/Materials Research Science and Engineering Center (DMR-1120296) through the Cornell Center for Materials Research (CCMR), as well as the NSF/Nanoscale Science and Engineering Center Program through the Cornell Center for Nanoscale Systems. We also acknowledge NSF support through use of the Cornell Nanofabrication Facility/National Nanofabrication Infrastructure Network and the CCMR facilities. Patent disclosures have been filed on behalf of the authors regarding the use of the spin Hall effect in Ta for magnetic memory and logic applications.

Supplementary Materials

www.sciencemag.org/cgi/content/full/336/6081/555/DCl

Materials and Methods

Supplementary Text

Figs. SI to S5

Reference (44)

20 December 2011; accepted 29 March 2012

10.1126/science.l218197

Science 336(6081):p 555-558, May 4, 2012.

Spin currents can apply useful torques in spintronic devices. The spin Hall effect has been proposed as a source of spin current, but its modest strength has limited its usefulness. We report a giant spin Hall effect (SHE) in β-tantalum that generates spin currents intense enough to induce efficient spin-torque switching of ferromagnets at room temperature. We quantify this SHE by three independent methods and demonstrate spin-torque switching of both out-of-plane and in-plane magnetized layers. We furthermore implement a three-terminal device that uses current passing through a tantalum-ferromagnet bilayer to switch a nanomagnet, with a magnetic tunnel junction for read-out. This simple, reliable, and efficient design may eliminate the main obstacles to the development of magnetic memory and nonvolatile spin logic technologies.