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Wan Z, Qiu G, Ren H, Qian Q, Li Y, Xu D, Zhou J, Zhou J, Zhou B, Wang L, Yang TH, Sofer Z, Huang Y, Wang KL, Duan X. Unconventional superconductivity in chiral molecule-TaS 2 hybrid superlattices. Nature 2024:10.1038/s41586-024-07625-4. [PMID: 38926586 DOI: 10.1038/s41586-024-07625-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 05/29/2024] [Indexed: 06/28/2024]
Abstract
Chiral superconductors, a unique class of unconventional superconductors in which the complex superconducting order parameter winds clockwise or anticlockwise in the momentum space1, represent a topologically non-trivial system with intrinsic time-reversal symmetry breaking (TRSB) and direct implications for topological quantum computing2,3. Intrinsic chiral superconductors are extremely rare, with only a few arguable examples, including UTe2, UPt3 and Sr2RuO4 (refs. 4-7). It has been suggested that chiral superconductivity may exist in non-centrosymmetric superconductors8,9, although such non-centrosymmetry is uncommon in typical solid-state superconductors. Alternatively, chiral molecules with neither mirror nor inversion symmetry have been widely investigated. We suggest that an incorporation of chiral molecules into conventional superconductor lattices could introduce non-centrosymmetry and help realize chiral superconductivity10. Here we explore unconventional superconductivity in chiral molecule intercalated TaS2 hybrid superlattices. Our studies reveal an exceptionally large in-plane upper critical field Bc2,|| well beyond the Pauli paramagnetic limit, a robust π-phase shift in Little-Parks measurements and a field-free superconducting diode effect (SDE). These experimental signatures of unconventional superconductivity suggest that the intriguing interplay between crystalline atomic layers and the self-assembled chiral molecular layers may lead to exotic topological materials. Our study highlights that the hybrid superlattices could lay a versatile path to artificial quantum materials by combining a vast library of layered crystals of rich physical properties with the nearly infinite variations of molecules of designable structural motifs and functional groups11.
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Affiliation(s)
- Zhong Wan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Gang Qiu
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Huaying Ren
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Qi Qian
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yaochen Li
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Dong Xu
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jingyuan Zhou
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jingxuan Zhou
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Boxuan Zhou
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Laiyuan Wang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Ting-Hsun Yang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Zdeněk Sofer
- Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Yu Huang
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA.
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.
| | - Kang L Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles, Los Angeles, CA, USA.
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, CA, USA.
| | - Xiangfeng Duan
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
- California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA, USA.
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Li C, Zhao YF, Vera A, Lesser O, Yi H, Kumari S, Yan Z, Dong C, Bowen T, Wang K, Wang H, Thompson JL, Watanabe K, Taniguchi T, Reifsnyder Hickey D, Oreg Y, Robinson JA, Chang CZ, Zhu J. Proximity-induced superconductivity in epitaxial topological insulator/graphene/gallium heterostructures. NATURE MATERIALS 2023; 22:570-575. [PMID: 36781950 DOI: 10.1038/s41563-023-01478-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 01/12/2023] [Indexed: 05/05/2023]
Abstract
The introduction of superconductivity to the Dirac surface states of a topological insulator leads to a topological superconductor, which may support topological quantum computing through Majorana zero modes1,2. The development of a scalable material platform is key to the realization of topological quantum computing3,4. Here we report on the growth and properties of high-quality (Bi,Sb)2Te3/graphene/gallium heterostructures. Our synthetic approach enables atomically sharp layers at both hetero-interfaces, which in turn promotes proximity-induced superconductivity that originates in the gallium film. A lithography-free, van der Waals tunnel junction is developed to perform transport tunnelling spectroscopy. We find a robust, proximity-induced superconducting gap formed in the Dirac surface states in 5-10 quintuple-layer (Bi,Sb)2Te3/graphene/gallium heterostructures. The presence of a single Abrikosov vortex, where the Majorana zero modes are expected to reside, manifests in discrete conductance changes. The present material platform opens up opportunities for understanding and harnessing the application potential of topological superconductivity.
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Affiliation(s)
- Cequn Li
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Yi-Fan Zhao
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Alexander Vera
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Omri Lesser
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Hemian Yi
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Shalini Kumari
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Zijie Yan
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Chengye Dong
- 2-Dimensional Crystal Consortium, The Pennsylvania State University, University Park, PA, USA
| | - Timothy Bowen
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Ke Wang
- Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Haiying Wang
- Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Jessica L Thompson
- Department of Chemistry, The Pennsylvania State University, University Park, PA, USA
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Danielle Reifsnyder Hickey
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
- Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
- Department of Chemistry, The Pennsylvania State University, University Park, PA, USA
| | - Yuval Oreg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Joshua A Robinson
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
- 2-Dimensional Crystal Consortium, The Pennsylvania State University, University Park, PA, USA
- Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
- Department of Chemistry, The Pennsylvania State University, University Park, PA, USA
| | - Cui-Zu Chang
- Department of Physics, The Pennsylvania State University, University Park, PA, USA
| | - Jun Zhu
- Department of Physics, The Pennsylvania State University, University Park, PA, USA.
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, USA.
- 2-Dimensional Crystal Consortium, The Pennsylvania State University, University Park, PA, USA.
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