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We conducted a high-throughput search for topological magnetic materials across 522 new, experimentally reported commensurate magnetic structures from MAGNDATA, doubling the number of available materials on the Topological Magnetic Materials database. This brings up to date the previous studies. For each material, we performed first-principles electronic calculations and diagnosed the topology as a function of the HubbardUparameter. Our high-throughput calculation led us to the prediction of 250 experimentally relevant topologically nontrivial materials, which represent 47.89% of the newly analyzed materials. We present five remarkable examples of these materials, each showcasing a different topological phase: Mn2AlB2(BCSID 1.508), which exhibits a nodal line semimetal to topological insulator transition as a function of SOC; CaMnSi (BCSID 0.599), a narrow gap axion insulator; UAsS (BCSID 0.594), a 5f-orbital Weyl semimetal; CsMnF4(BCSID 0.327), a material presenting a new type of quasi-symmetry protected closed nodal surface; and FeCr2S4(BCSID 0.613), a symmetry-enforced semimetal with double Weyls and spin-polarized surface states.
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Electronic anisotropy and rotational symmetry breaking at a Weyl semimetal/spin ice interface
In magnetic pyrochlore materials, the interplay of spin-orbit coupling, electronic correlations, and geometrical frustration gives rise to exotic quantum phases, including topological semimetals and spin ice. While these phases have been observed in isolation, the interface-driven phenomena emerging from their interaction have never been realized previously. Here, we report on the discovery of interfacial electronic anisotropy and rotational symmetry breaking at a heterostructure consisting of the Weyl semimetal Eu2Ir2O7and spin ice Dy2Ti2O7. Subjected to magnetic fields, we unveil a sixfold anisotropic transport response that is theoretically accounted by a Kondo-coupled heterointerface, where the spin ice’s field-tuned magnetism induces electron scattering in the Weyl semimetal’s topological Fermi-arc states. Furthermore, at elevated magnetic fields, we reveal a twofold anisotropic response indicative of the emergence of a symmetry-broken many-body state. This discovery showcases the potential of pyrochlore frustrated magnet/topological semimetal heterostructures in search of emergent interfacial phenomena.
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- Award ID(s):
- 1941569
- PAR ID:
- 10643228
- Publisher / Repository:
- Science Advances
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 24
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1126/sciadv.adr6202
