Orbital-hybridization-induced Ising-type superconductivity in a confined gallium layer

Hemian Yi; Yunzhe Liu; Chengye Dong; Yiheng Yang; Zi-Jie Yan; Zihao Wang; Lingjie Zhou; Dingsong Wu; Houke Chen; Stephen Paolini; Bing Xia; Bomin Zhang; Xiaoda Liu; Hongtao Rong; Annie G Wang; Saswata Mandal; Kaijie Yang; Benjamin N Katz; Lunhui Hu; Jieyi Liu; Tien-Lin Lee; Vincent H Crespi; Yuanxi Wang; Yulin Chen; Joshua A Robinson; Chao-Xing Liu; Cui-Zu Chang

doi:10.1038/s41563-026-02573-y

Orbital-hybridization-induced Ising-type superconductivity in a confined gallium layer

Nat Mater. 2026 Jul;25(7):1175-1181. doi: 10.1038/s41563-026-02573-y. Epub 2026 Apr 13.

Authors

Hemian Yi^#^{1

2}, Yunzhe Liu^#³, Chengye Dong^#⁴, Yiheng Yang^#⁵, Zi-Jie Yan³, Zihao Wang³, Lingjie Zhou³, Dingsong Wu⁵, Houke Chen⁵, Stephen Paolini³, Bing Xia³, Bomin Zhang³, Xiaoda Liu³, Hongtao Rong³, Annie G Wang³, Saswata Mandal³, Kaijie Yang³, Benjamin N Katz³, Lunhui Hu⁶, Jieyi Liu^{5

7}, Tien-Lin Lee⁷, Vincent H Crespi³, Yuanxi Wang⁸, Yulin Chen⁵, Joshua A Robinson^{3

4}, Chao-Xing Liu⁹, Cui-Zu Chang¹⁰

Affiliations

¹ Department of Physics, The Pennsylvania State University, University Park, PA, USA. hemianyi@sjtu.edu.cn.
² Tsung-Dao Lee Institute and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China. hemianyi@sjtu.edu.cn.
³ Department of Physics, The Pennsylvania State University, University Park, PA, USA.
⁴ Department of Materials Science and Engineering and Two-dimensional Crystal Consortium, The Pennsylvania State University, University Park, PA, USA.
⁵ Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, UK.
⁶ Center for Correlated Matter and School of Physics, Zhejiang University, Hangzhou, China.
⁷ Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK.
⁸ Department of Physics, University of North Texas, Denton, TX, USA.
⁹ Department of Physics, The Pennsylvania State University, University Park, PA, USA. cxl56@psu.edu.
¹⁰ Department of Physics, The Pennsylvania State University, University Park, PA, USA. cxc955@psu.edu.

^# Contributed equally.

PMID: 41975080
DOI: 10.1038/s41563-026-02573-y

Abstract

In low-dimensional superconductors, the interplay between quantum confinement and interfacial hybridization effects can reshape Cooper-pair wavefunctions and give rise to unconventional superconducting states. Here we use plasma-free confinement epitaxy assisted by a carbon buffer layer to synthesize a gallium trilayer sandwiched between graphene and a 6H-SiC(0001) substrate. Within this confined gallium layer, we demonstrate interfacial Ising-type superconductivity driven by atomic orbital hybridization. Electrical transport measurements reveal that the in-plane upper critical magnetic field reaches ~21.98 T at T = 400 mK, approximately 3.38 times the Pauli paramagnetic limit. Angle-resolved photoemission spectroscopy measurements, combined with theoretical calculations, confirm the presence of split Fermi surfaces with Ising-type spin textures at the K and K' valleys of the confined gallium layer, originating from strong hybridization with the SiC substrate. This work establishes a strategy for realizing unconventional pairing wavefunctions through the synergistic combination of quantum confinement and interfacial hybridization effects.

Abstract

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