Insulator-to-Metal Transition and Isotropic Gigantic Magnetoresistance in Layered Magnetic Semiconductors

Gokul Acharya; Bimal Neupane; Chia-Hsiu Hsu; Xian P Yang; David Graf; Eun Sang Choi; Krishna Pandey; Md Rafique Un Nabi; Santosh Karki Chhetri; Rabindra Basnet; Sumaya Rahman; Jian Wang; Zhengxin Hu; Bo Da; Hugh O H Churchill; Guoqing Chang; M Zahid Hasan; Yuanxi Wang; Jin Hu

doi:10.1002/adma.202410655

Insulator-to-Metal Transition and Isotropic Gigantic Magnetoresistance in Layered Magnetic Semiconductors

Adv Mater. 2024 Nov;36(48):e2410655. doi: 10.1002/adma.202410655. Epub 2024 Oct 11.

Authors

Gokul Acharya¹, Bimal Neupane², Chia-Hsiu Hsu^{3

4}, Xian P Yang⁵, David Graf⁶, Eun Sang Choi⁶, Krishna Pandey⁷, Md Rafique Un Nabi^{1

8}, Santosh Karki Chhetri¹, Rabindra Basnet¹, Sumaya Rahman⁷, Jian Wang⁹, Zhengxin Hu^{10

11}, Bo Da¹⁰, Hugh O H Churchill^{1

7

8}, Guoqing Chang³, M Zahid Hasan^{5

12

13}, Yuanxi Wang², Jin Hu^{1

7

8}

Affiliations

¹ Department of Physics, University of Arkansas, Fayetteville, AR, 72701, USA.
² Department of Physics, University of North Texas, Denton, TX, 76205, USA.
³ Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
⁴ Quantum Materials Science Unit, Okinawa Institute of Science and Technology (OIST), Okinawa, 904-0495, Japan.
⁵ Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
⁶ National High Magnetic Field Lab, Tallahassee, FL, 32310, USA.
⁷ Materials Science and Engineering Program, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, 72701, USA.
⁸ MonArk NSF Quantum Foundry, University of Arkansas, Fayetteville, AR, 72701, USA.
⁹ Department of Chemistry and Biochemistry, Wichita State University, Wichita, KS, 67260, USA.
¹⁰ Center for Basic Research on Materials, National Institute for Materials Science (NIMS), Tsukuba-city, Ibaraki, 305-0047, Japan.
¹¹ Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
¹² Princeton Institute for Science and Technology of Materials, Princeton University, Princeton, NJ, 08544, USA.
¹³ Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.

Abstract

Magnetotransport, the response of electrical conduction to external magnetic field, acts as an important tool to reveal fundamental concepts behind exotic phenomena and plays a key role in enabling spintronic applications. Magnetotransport is generally sensitive to magnetic field orientations. In contrast, efficient and isotropic modulation of electronic transport, which is useful in technology applications such as omnidirectional sensing, is rarely seen, especially for pristine crystals. Here a strategy is proposed to realize extremely strong modulation of electron conduction by magnetic field which is independent of field direction. GdPS, a layered antiferromagnetic semiconductor with resistivity anisotropies, supports a field-driven insulator-to-metal transition with a paradoxically isotropic gigantic negative magnetoresistance insensitive to magnetic field orientations. This isotropic magnetoresistance originates from the combined effects of a near-zero spin-orbit coupling of Gd³⁺-based half-filling f-electron system and the strong on-site f-d exchange coupling in Gd atoms. These results not only provide a novel material system with extraordinary magnetotransport that offers a missing block for antiferromagnet-based ultrafast and efficient spintronic devices, but also demonstrate the key ingredients for designing magnetic materials with desired transport properties for advanced functionalities.

Keywords: exchange splitting; insulator‐to‐metal transition; isotropic magneto‐transport; magnetoresistance.

Abstract

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