Abstract
Since the initial discovery of 2D van der Waals (vdW) materials, significant effort has been made to incorporate the three properties of magnetism, band structure topology, and strong electron correlations—to leverage emergent quantum phenomena and expand their potential applications. However, the discovery of a single vdW material that intrinsically hosts all three ingredients has remained an outstanding challenge. Here, the discovery of a Kondo-interacting topological antiferromagnet is reported in the vdW 5f electron system UOTe. It has a high antiferromagnetic (AFM) transition temperature of 150 K, with a unique AFM configuration that breaks the combined parity and time reversal (PT) symmetry in an even number of layers while maintaining zero net magnetic moment. This angle-resolved photoemission spectroscopy (ARPES) measurements reveal Dirac bands near the Fermi level, which combined with the theoretical calculations demonstrate UOTe as an AFM Dirac semimetal. Within the AFM order, the presence of the Kondo interaction is observed, as evidenced by the emergence of a 5f flat band near the Fermi level below 100 K and hybridization between the Kondo band and the Dirac band. The density functional theory calculations in its bilayer form predict UOTe as a rare example of a fully-compensated AFM Chern insulator.
| Original language | English |
|---|---|
| Journal | Advanced Materials |
| DOIs | |
| State | Accepted/In press - 2024 |
Funding
C.B., S.M., and M.L. contributed equally to this work. The authors acknowledge fruitful discussions with Paul Canfield, Lei Chen, Daniel Dessau, Ni Ni, Priscila F. S. Rosa, Qimiao Si, Kai Sun, and Jianxin Zhu. The work at Washington University was supported by the National Science Foundation (NSF) Division of Materials Research Award DMR\u20102236528. C. Broyles acknowledges the NRT LinQ, supported by the NSF under Grant No. 2152221. S.M. and S.C. from Howard University, work supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences Grant No. DE\u2010SC0022216. G.A. and J.G. from Howard University would like to thank the IBM\u2010HBCU Quantum Center for financial support. This research at Howard University used the resources of Accelerate ACCESS PHYS220127 and PHYS2100073. M.L. acknowledges the Harvard Quantum Initiative Postdoctoral Fellowship and the assistance of Austin Akey, Jules Gardener, and Timothy J. Cavanaugh from the Center for Nanoscale Systems at Harvard in conducting the EDX, SEM, and TEM measurement. A.V. and J.A. were supported by the Center for Advancement of Topological Semimetals, an Energy Frontier Research Center funded by the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences, through Ames Laboratory under contract No. DE\u2010AC02\u201007CH11358. P.K. acknowledges the support from NSF (DMR\u20102105048). J.E.H. was supported by the Gordon and Betty Moore Foundation\u2019s EPiQS Initiative through grants GBMF10215. The work in S.Y.X.\u2019s group was partly supported through the Center for the Advancement of Topological Semimetals, an Energy Frontier Research Center funded by the US Department of Energy (DOE), Office of Science (fabrication and measurements), through the Ames National Laboratory (Contract No. DE\u2010AC\u20100207CH11358), partly through the Air Force Office of Scientific Research (Grant No. FA9550\u201023\u20101\u20100040 for data analysis), and partly through the National Science Foundation (NSF; Career Grant No. DMR\u20102143177 for manuscript writing).The single crystal X\u2010ray structure determination was supported by the U.S. DOE Basic Energy Sciences via the grant DE\u2010SC0023648. D.L. and L.Y. are supported by the Air Force Office of Scientific Research (AFOSR) Grant No. FA9550\u201020\u20101\u20100255. The simulation used Purdue Anvil CPU at Purdue University through allocation DMR100005 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services Support (ACCESS) program. Research at the University of Arizona was supported by the NSF under Award No. DMR\u20102338229. Photoemission used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE\u2010AC02\u201005CH11231. The work at Oak Ridge National Laboratory (ORNL) was supported by the U.S. DOE, Office of Science, Office of Basic Energy Sciences, Early Career Research Program Award KC0402020, under Contract DE\u2010AC05\u201000OR22725. This research used resources at the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by ORNL.
| Funders | Funder number |
|---|---|
| IBM‐HBCU Quantum Center | |
| Oak Ridge National Laboratory | |
| Howard University | |
| Center for Nanoscale Systems at Harvard | |
| Office of Science | DE‐AC02‐05CH11231 |
| Office of Science | |
| Air Force Office of Scientific Research | FA9550‐23‐1‐0040, DMR‐2143177 |
| Air Force Office of Scientific Research | |
| National Science Foundation | DMR‐2236528 |
| National Science Foundation | |
| U.S. Department of Energy | DE‐AC05‐00OR22725, KC0402020 |
| U.S. Department of Energy | |
| Basic Energy Sciences | DE‐SC0023648, DE‐SC0022216, FA9550‐20‐1‐0255, DMR‐2338229 |
| Basic Energy Sciences | |
| Ames National Laboratory | DE‐AC02‐07CH11358, DMR‐2105048 |
| Ames National Laboratory | |
| NRT LinQ | 2152221 |
| Gordon and Betty Moore Foundation | GBMF10215 |
| Gordon and Betty Moore Foundation |
Keywords
- antiferromagnet
- topological
- van der Waals