Large anomalous Hall effect and anisotropic magnetoresistance in intrinsic nanoscale spin-valve-type structure of an antiferromagnet

Dong Gun Oh; Jong Hyuk Kim; Mi Kyung Kim; Ki Won Jeong Hyun Jun Shin; Jae Min Hong; Jin Seok Kim; Kyungsun Moon; Nara Lee; Young Jai Choi

arXiv · 2203.10952

Large anomalous Hall effect and anisotropic magnetoresistance in intrinsic nanoscale spin-valve-type structure of an antiferromagnet

Dong Gun Oh·Jong Hyuk Kim·Mi Kyung Kim·Ki Won Jeong Hyun Jun Shin·Jae Min Hong·Jin Seok Kim·Kyungsun Moon·Nara Lee·Young Jai Choi

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Abstract

A spin valve is a prototype of spin-based electronic devices found on ferromagnets, in which an antiferromagnet plays a supporting role. Recent findings in antiferromagnetic spintronics show that an antiferromagnetic order in single-phase materials solely governs dynamic transport, and antiferromagnets are considered promising candidates for spintronic technology. In this work, we demonstrated antiferromagnet-based spintronic functionality on an itinerant Ising antiferromagnet of Ca0.9Sr0.1Co2As2 by integrating nanoscale spin-valve-type structure and investigating anisotropic magnetic properties driven by spin-flips. Multiple stacks of 1 nm thick spin-valve-like unit are intrinsically embedded in the antiferromagnetic spin structure. In the presence of a rotating magnetic field, a new type of the spin-valve-like operation was observed for large anomalous Hall conductivity and anisotropic magnetoresistance, whose effects are maximized above the spin-flip transition. In addition, a joint experimental and theoretical study provides an efficient tool to read out various spin states, which scheme can be useful for implementing extensive spintronic applications.

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Dong Gun Oh, Jong Hyuk Kim, Mi Kyung Kim, Ki Won Jeong Hyun Jun Shin, Jae Min Hong, Jin Seok Kim, Kyungsun Moon, Nara Lee, Young Jai Choi. 2022-03-21. Large anomalous Hall effect and anisotropic magnetoresistance in intrinsic nanoscale spin-valve-type structure of an antiferromagnet. https://arxiv.org/abs/2203.10952

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