中国物理B ›› 2025, Vol. 34 ›› Issue (11): 117402-117402.doi: 10.1088/1674-1056/ade24f

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Lithium-intercalation-induced structural evolution and superconductivity modulation in 2H-LixTaSe2

Lijia Zhou(周立佳)1, Xiangjiang Dong(董祥江)2, Qiang Li(李强)1, Xiaojun Kuang(匡小军)3, and Xianran Xing(邢献然)1,†   

  1. 1 Beijing Advanced Innovation Center for Materials Genome Engineering and Institute of Solid-State Chemistry, University of Science and Technology Beijing, Beijing 100083, China;
    2 Center for High-Pressure Science and Technology Advanced Research, Beijing 100093, China;
    3 Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China
  • 收稿日期:2025-05-06 修回日期:2025-05-29 接受日期:2025-06-09 发布日期:2025-10-30
  • 基金资助:
    This research was supported by the National Natural Science Foundation of China (Grant Nos. 22090042 and 22175018).

Lithium-intercalation-induced structural evolution and superconductivity modulation in 2H-LixTaSe2

Lijia Zhou(周立佳)1, Xiangjiang Dong(董祥江)2, Qiang Li(李强)1, Xiaojun Kuang(匡小军)3, and Xianran Xing(邢献然)1,†   

  1. 1 Beijing Advanced Innovation Center for Materials Genome Engineering and Institute of Solid-State Chemistry, University of Science and Technology Beijing, Beijing 100083, China;
    2 Center for High-Pressure Science and Technology Advanced Research, Beijing 100093, China;
    3 Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China
  • Received:2025-05-06 Revised:2025-05-29 Accepted:2025-06-09 Published:2025-10-30
  • Contact: Xianran Xing E-mail:xing@ustb.edu.cn
  • Supported by:
    This research was supported by the National Natural Science Foundation of China (Grant Nos. 22090042 and 22175018).

摘要: We systematically investigated the structural and superconducting properties of polycrystalline 2H-Li$_{x}$TaSe$_{2}$ ($0.1 \le x \le 1.0$) synthesized via a high-temperature solid-state reaction. Lithium (Li) intercalation induces an expansion along the $c$-axis and intralayer distortions within the Ta—Se coordination network. The superconducting transition temperature ($T_{\rm c}$) is increased to 2.95 K at $x = 0.1$ driven by the synergistic enhancement of the electronic density of states at the Fermi level, $N(E_{\rm F})$, and strengthened electron—phonon coupling. With further Li doping, although $N(E_{\rm F})$ continues to increase, lattice stiffening and pronounced distortions in the Ta—Se coordination polyhedra weaken the electron—phonon interaction, ultimately suppressing superconductivity. These findings highlight the critical role of intralayer structural modulation in governing structure-tunable superconductivity in layered materials.

关键词: superconductivity, Li intercalation, local structural distortion

Abstract: We systematically investigated the structural and superconducting properties of polycrystalline 2H-Li$_{x}$TaSe$_{2}$ ($0.1 \le x \le 1.0$) synthesized via a high-temperature solid-state reaction. Lithium (Li) intercalation induces an expansion along the $c$-axis and intralayer distortions within the Ta—Se coordination network. The superconducting transition temperature ($T_{\rm c}$) is increased to 2.95 K at $x = 0.1$ driven by the synergistic enhancement of the electronic density of states at the Fermi level, $N(E_{\rm F})$, and strengthened electron—phonon coupling. With further Li doping, although $N(E_{\rm F})$ continues to increase, lattice stiffening and pronounced distortions in the Ta—Se coordination polyhedra weaken the electron—phonon interaction, ultimately suppressing superconductivity. These findings highlight the critical role of intralayer structural modulation in governing structure-tunable superconductivity in layered materials.

Key words: superconductivity, Li intercalation, local structural distortion

中图分类号:  (Metals; alloys and binary compounds)

  • 74.70.Ad
74.62.Bf (Effects of material synthesis, crystal structure, and chemical composition) 74.25.Dw (Superconductivity phase diagrams)