Tunable topological effects in Ga doped Mn3Sn thin films

ORAL

Abstract

Mn3X(X=Sn, Ga, Ge) antiferromagnetic (AFM) Weyl semimetals have attracted significant research due to their large Berry phase effects and potential for applications[1,2]. The temperature range for the anti-chiral magnetic phase with large topological effects varies for each of these materials, the highest temperature being the Neel temperature (TN). Thin film forms of Mn3Sn are routinely studied [3], however, in Mn3Sn the anti-chiral magnetic phase has a limited temperature range (≈260-420K). To fully exploit the device possibilities, ranging from AFM spintronics [1-3] to unconventional superconducting spintronics based on Mn3X/superconductor structures [4], one needs to engineer these Mn3X thin film systems maximizing the Berry phase effects over a wide temperature range. In this work we present sputtered Mn3Sn1-xGax thin films in which the anti-chiral magnetic phase of Mn3Sn is systematically modified with Ga doping. Our detailed structural characterization of Mn3Sn1-xGax reveals a systematic linear variation of the lattice parameters between Mn3Sn (for x=0) and Mn3Ga (for x=1) satisfying Vegard’s law of a substitutional solid solution. Temperature dependent Hall effect and magnetization measurements confirm a giant enhancement of anomalous Hall conductivity over a wide temperature range (extending from »500K down to at least 10K), and a systematic enhancement of TN (from ≈420K to ≈500K) with Ga addition. In conclusion, our work presents a route for engineering topological effects in Mn3X systems.

* The work at the Institute for Quantum Matter, an Energy Frontier Research Center was funded by DOE, Office of Science, Basic Energy Sciences under Award # DE-SC0019331. This work was partially supported by JST-Mirai Program (JPMJMI20A1), JST-CREST (JPMJCR18T3), and New Energy and Industrial Technology Development Organization (NEDO). The use of the facilities of the Materials Design and Characterization Laboratory at the Institute for Solid State Physics, The University of Tokyo, is gratefully acknowledged.

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Publication: None

Presenters

  • M. Raju

    Johns Hopkins University

Authors

  • M. Raju

    Johns Hopkins University

  • Tomoya Higo

    The University of Tokyo, University of Tokyo, Univ of Tokyo, Dept. of Phys. Univ. of Tokyo

  • Daisuke Nishio-Hamane

    University of Tokyo, The University of Tokyo

  • Collin L Broholm

    John Hopkins University, Johns Hopkins University

  • Satoru Nakatsuji

    Univesity of Tokyo, University of Tokyo, The University of Tokyo & IQM, Johns Hopkins University, The University of Tokyo