Reversible non-volatile electronic switching in a near-room-temperature van der Waals ferromagnet

Han Wu; Lei Chen; Paul Malinowski; Bo Gyu Jang; Qinwen Deng; Kirsty Scott; Jianwei Huang; Jacob P C Ruff; Yu He; Xiang Chen; Chaowei Hu; Ziqin Yue; Ji Seop Oh; Xiaokun Teng; Yucheng Guo; Mason Klemm; Chuqiao Shi; Yue Shi; Chandan Setty; Tyler Werner; Makoto Hashimoto; Donghui Lu; Turgut Yilmaz; Elio Vescovo; Sung-Kwan Mo; Alexei Fedorov; Jonathan D Denlinger; Yaofeng Xie; Bin Gao; Junichiro Kono; Pengcheng Dai; Yimo Han; Xiaodong Xu; Robert J Birgeneau; Jian-Xin Zhu; Eduardo H da Silva Neto; Liang Wu; Jiun-Haw Chu; Qimiao Si; Ming Yi

doi:10.1038/s41467-024-46862-z

Reversible non-volatile electronic switching in a near-room-temperature van der Waals ferromagnet

Nat Commun. 2024 Mar 28;15(1):2739. doi: 10.1038/s41467-024-46862-z.

Authors

Han Wu¹, Lei Chen¹, Paul Malinowski², Bo Gyu Jang^{3

4}, Qinwen Deng⁵, Kirsty Scott^{6

7

8

9}, Jianwei Huang¹, Jacob P C Ruff¹⁰, Yu He¹¹, Xiang Chen¹¹, Chaowei Hu^{2

12}, Ziqin Yue¹, Ji Seop Oh^{1

12}, Xiaokun Teng¹, Yucheng Guo¹, Mason Klemm¹, Chuqiao Shi¹³, Yue Shi², Chandan Setty¹, Tyler Werner⁹, Makoto Hashimoto¹⁴, Donghui Lu¹⁴, Turgut Yilmaz¹⁵, Elio Vescovo¹⁵, Sung-Kwan Mo¹⁶, Alexei Fedorov¹⁶, Jonathan D Denlinger¹⁶, Yaofeng Xie¹, Bin Gao¹, Junichiro Kono^{1

13

17}, Pengcheng Dai¹, Yimo Han¹³, Xiaodong Xu^{2

12}, Robert J Birgeneau^{11

18

19}, Jian-Xin Zhu³, Eduardo H da Silva Neto^{6

7

8

9}, Liang Wu⁵, Jiun-Haw Chu², Qimiao Si¹, Ming Yi²⁰

Affiliations

¹ Department of Physics and Astronomy and Rice Center for Quantum Materials, Rice University, Houston, TX, USA.
² Department of Physics, University of Washington, Seattle, WA, USA.
³ Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA.
⁴ Department of Advanced Materials Engineering for Information and Electronics, Kyung Hee University, Yongin, Republic of Korea.
⁵ Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, USA.
⁶ Department of Physics, Yale University, New Haven, CT, USA.
⁷ Energy Sciences Institute, Yale University, West Haven, CT, USA.
⁸ Department of Physics and Astronomy, University of California, Davis, CA, USA.
⁹ Department of Applied Physics, Yale University, New Haven, CT, USA.
¹⁰ Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY, USA.
¹¹ Department of Physics, University of California, Berkeley, CA, USA.
¹² Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA.
¹³ Department of Materials Science and NanoEngineering, Rice University, Houston, TX, USA.
¹⁴ Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
¹⁵ National Synchrotron Light Source II, Brookhaven National Lab, Upton, NY, USA.
¹⁶ Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
¹⁷ Departments of Electrical and Computer Engineering, Rice University, Houston, TX, USA.
¹⁸ Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
¹⁹ Department of Materials Science and Engineering, University of California, Berkeley, CA, USA.
²⁰ Department of Physics and Astronomy and Rice Center for Quantum Materials, Rice University, Houston, TX, USA. mingyi@rice.edu.

Abstract

Non-volatile phase-change memory devices utilize local heating to toggle between crystalline and amorphous states with distinct electrical properties. Expanding on this kind of switching to two topologically distinct phases requires controlled non-volatile switching between two crystalline phases with distinct symmetries. Here, we report the observation of reversible and non-volatile switching between two stable and closely related crystal structures, with remarkably distinct electronic structures, in the near-room-temperature van der Waals ferromagnet Fe_5-δGeTe₂. We show that the switching is enabled by the ordering and disordering of Fe site vacancies that results in distinct crystalline symmetries of the two phases, which can be controlled by a thermal annealing and quenching method. The two phases are distinguished by the presence of topological nodal lines due to the preserved global inversion symmetry in the site-disordered phase, flat bands resulting from quantum destructive interference on a bipartite lattice, and broken inversion symmetry in the site-ordered phase.

Grants and funding

DE-SC0021421/DOE | Advanced Research Projects Agency - Energy (Advanced Research Projects Agency - Energy - U.S. Department of Energy)