Unconventional insulator-to-metal phase transition in Mn3Si2Te6
The nodal-line semiconductor Mn<sub>3</sub>Si<sub>2</sub>Te<sub>6</sub> is generating enormous excitment due to the recent discovery of a field-driven insulator-to-metal transition and associated colossal magnetoresistance as well as evidence for a new type of quantum state involving chiral orbital currents. Strikingly, these qualities persist even in the absence of traditional Jahn-Teller distortions and double-exchange mechanisms, raising questions about exactly how and why magnetoresistance occurs along with conjecture as to the likely signatures of loop currents. Here, we measured the infrared response of Mn<sub>3</sub>Si<sub>2</sub>Te<sub>6</sub> across the magnetic ordering and field-induced insulator-to-metal transitions in order to explore colossal magnetoresistance in the absence of Jahn-Teller and double-exchange interactions. Rather than a traditional metal with screened phonons, the field-driven insulator-to-metal transition leads to a weakly metallic state with localized carriers. Our spectral data are fit by a percolation model, providing evidence for electronic inhomogeneity and phase separation. Modeling also reveals a frequency-dependent threshold field for carriers contributing to colossal magnetoresistance which we discuss in terms of polaron formation, chiral orbital currents, and short-range spin fluctuations. These findings enhance the understanding of insulator-to-metal transitions in new settings and open the door to the design of unconventional colossal magnetoresistant materials.
Authors
- Kristjan Haule (ORCID: https://orcid.org/0000-0002-2284-1551)
- Mykhaylo Ozerov (ORCID: https://orcid.org/0000-0002-5470-1158)
- Turan Birol (ORCID: https://orcid.org/0000-0001-5174-3320)
- Christopher C. Homes (ORCID: https://orcid.org/0000-0001-7087-756X)
- Amartyajyoti Saha (ORCID: https://orcid.org/0000-0001-9228-3340)
- Choongjae Won (ORCID: https://orcid.org/0000-0003-1148-0006)
- Elbio R. Dagotto (ORCID: https://orcid.org/0000-0001-6007-5694)
- Chandan De (ORCID: https://orcid.org/0000-0003-1759-1137)
- J. L. Musfeldt (ORCID: https://orcid.org/0000-0002-6241-823X)
- Sang‐Wook Cheong (ORCID: https://orcid.org/0000-0001-9905-6175)
- Ling-Fang Lin (ORCID: https://orcid.org/0000-0003-0045-6537)
- Yang Zhang (ORCID: https://orcid.org/0000-0003-3623-5883)
- K. Smith (ORCID: https://orcid.org/0000-0001-6635-3915)
- Yanhong Gu
Institutions
- Rutgers, The State University of New Jersey (US)
- Florida State University (US)
- Pohang University of Science and Technology (KR)
- Oak Ridge National Laboratory (US)
- University of Minnesota (US)
- Okinawa Institute of Science and Technology Graduate University (JP)
- Brookhaven National Laboratory (US)
- Knoxville College (US)
- National High Magnetic Field Laboratory (US)
- University of Tennessee at Knoxville (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2024-09-16
- DOI
- https://doi.org/10.1038/s41467-024-52350-1
- Citations
- 11
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.29
Funders
- National Science Foundation
- U.S. Department of Energy
- Gordon and Betty Moore Foundation
- University of Minnesota
- National High Magnetic Field Laboratory
- National Research Foundation
- National Research Foundation of Korea
- Ministry of Science and ICT, South Korea
- Office of Science
- Division of Materials Research
- Basic Energy Sciences
- High Magnetic Field Laboratory, Chinese Academy of Sciences
- Brookhaven National Laboratory