High-field triplet superconductivity in a transition metal dichalcogenide superlattice

Nature Physics (2026)Cite this article The wavefunction of Cooper pairs in superconductors is characterized by the spin and orbital angular momenta of their constituent electrons. Given the fermionic nature of electrons, a Cooper pair must be antisymmetric with respect to the exchange of the particles that compose it. Nearly all stoichiometric superconductors host spin-singlet Cooper pairs with zero angular momentum and spin. An important exception are a small number of uranium-based heavy fermion materials believed to support odd angular momentum, spin-triplet states. Therefore, discovery of different triplet superconducting materials is important for understanding unconventional superconductivity. Here we show that the natural superlattice material BaTa2S5 without doping supports a high-field, clean-limit superconducting state persisting to at least 60 T. Arising at a first-order transition out of an Ising-like superconducting phase, this state is highly two-dimensional and consistent with a field-induced triplet pairing. These results suggest that a broad family of spin-triplet, two-dimensional, d-electron superconductors can be created by tuning of spin–orbit coupling, dimensionality and electronic quality. Looking forward, the rare presence of multiple superconducting phases along with crystallographic symmetries supporting p- or f-wave pairing in these systems may lead to new materials for high-field and topological superconductivity.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutSource data for Figs. 1–4 and Supplementary Information are available upon request from corresponding authors. Source data are provided with this paper.Stewart, G. Heavy-fermion systems. Rev. Mod. Phys. 56, 755 (1984).Article ADS Google Scholar Klemm, R. A.

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Maier, P. Mueller, S. Lapidus and L. Ribaud. This work was funded, in part, by the Gordon and Betty Moore Foundation EPiQS Initiative (grant no. GBMF9070 to J.G.C (synthesis instrumentation and computation)), the US Department of Energy (DOE) Office of Science, Basic Energy Sciences, under award no. DE-SC0022028 (material development), the Office of Naval Research (ONR) under award no. N000142412407 (material analysis), ARO grant no. W911NF-24-1-0234 (measurement technique development) and the Center for Advancement of Topological Semimetals, an Energy Frontier Research Center funded by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), through the Ames Laboratory (contract no. DE-AC02-07CH11358) (pulsed-field experiments). A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by the National Science Foundation Cooperative Agreement no. DMR-1644779, the State of Florida and the DOE. Pulsed magnetic field measurements at Los Alamos National Laboratory were supported by the US Department of Energy BES ‘Science at 100T’ grant. We acknowledge the MIT SuperCloud63 and Lincoln Laboratory Supercomputing Center for providing HPC resources that have contributed to the results reported herein. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract no. DE-AC02-06CH11357.Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USAS. Y. Frank Zhao, Paul M. Neves, Joshua P. Wakefield, Shiang Fang, Alan Chen & Joseph G. CheckelskyDepartment of Physics and Quantum Materials Center, University of Maryland, College Park, MD, USAS. Y. Frank ZhaoNational High Magnetic Field Laboratory, LANL, Los Alamos, NM, USAJohanna C. PalmstromNational High Magnetic Field Laboratory, Tallahassee, FL, USADavid E. GrafHarvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USAAvi Auslender & David C. BellCenter for Nanoscale Systems, Harvard University, Cambridge, MA, USAAvi Auslender & David C. BellDepartment of Physics, University of Connecticut, Storrs, CT, USAPavel A. VolkovDepartment of Physics, Toho University, Funabashi, JapanTakehito SuzukiSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarS.Y.F.Z. synthesized and characterized the materials with support from T.S. S.Y.F.Z. performed and analysed the physical property measurements with P.M.N., J.P.W., A.C., D.E.G. (high d.c. magnetic fields) and P.M.N. and J.C.P. (pulsed magnetic fields). A.A. and D.C.B. performed the electron microscopy experiments. S.F. and S.Y.F.Z. performed the electronic structure calculations. P.A.V. and S.Y.F.Z. performed analytical calculations. S.Y.F.Z. and J.G.C. wrote the paper with contributions and discussions from all authors. J.G.C. supervised the project.Correspondence to S. Y. Frank Zhao or Joseph G. Checkelsky.The authors declare no competing interests.Nature Physics thanks Ni Ni and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.Symbol colors show cleanliness of superconductor as defined by ratio between Pippard coherence length ξ and mean-free-path l. Materials where this information is unavailable is shown in gray. Symbol shape and label color indicate material class. Multiphase superconductors showing phase transitions between SC states are indicated by yellow highlight. Superconductors with intrinsically inhomogeneous phases such as Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase are shown with stripes. Diagonal dotted lines show multiples of Pauli limit HP (Tc). Background color show cryogenic techniques necessary to reach Tc. Gr is abbreviation for graphene. ET is abbreviation for bis(ethylenedithio)-tetrathiafulvalene. The numerical prefix on interfacial superconductors indicate thickness of sample in van der Waals layers. Relevant references in Supplementary Information Section 10.Source dataSupplementary Discussion Sections 1–10, Tables 1–4 and Figs. 1–13.Source data for Fig. 1e,f.Source data for Fig. 2.Source data for Fig. 3.Source data for Fig. 4.Source data for Extended Data Fig. 1.Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsZhao, S.Y.F., Neves, P.M., Wakefield, J.P. et al. High-field triplet superconductivity in a transition metal dichalcogenide superlattice. Nat. Phys. (2026). https://doi.org/10.1038/s41567-026-03185-8Download citationReceived: 03 March 2025Accepted: 16 January 2026Published: 06 March 2026Version of record: 06 March 2026DOI: https://doi.org/10.1038/s41567-026-03185-8Anyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative