Physics Colloquium

Prof. Maxim Tsoi, UT-Austin

"Antiferromagnetic Spintronics"

4:00pm, The John A. Wheeler Lecture Hall (RLM 4.102). Coffee and cookies will be served at 3:45pm in RLM 4.102

Abstract: Interconnections between magnetic state and transport currents in ferromagnetic (F) heterostructures are the basis for spintronic applications, e.g. tunneling magnetoresistance and spin-transfer torque phenomena provide a means to read and write information in magnetic memory devices like STTRAM. Similar interconnections were proposed [1] to occur in systems where F-components are replaced with antiferromagnets (AFM). We demonstrated experimentally the existence of such interconnections in antiferromagnetic Mott insulator Sr2IrO4: first, we found a very large anisotropic magnetoresistance (AMR) which can be used to monitor (read) the magnetic state of AFM [2]; second, we demonstrated the feasibility of reversible resistive switching driven by high-density currents/high electric fields [3] which can be used for writing in AFM memory applications. These results support the feasibility of AFM spintronics where antiferromagnets are used in place of ferromagnets.

This work was supported in part by C-SPIN, one of six centers of STARnet, a Semiconductor Research Corporation program, sponsored by MARCO and DARPA and by NSF grant DMR-1207577.

[1] A. S. Núñez et al., Phys. Rev. B 73, 214426 (2006).
[2] C. Wang et al., Phys. Rev. X 4, 041034 (2014).
[3] C. Wang et al., arXiv1502.07982.