Scholarlink

<p>Boron-rich lithium borocarbides are promising candidates for phonon-mediated high-temperature superconductors due to their metallic <i>σ</i>-bonding electrons. Here, we use the cluster expansion method to identify energetically stable configurations (colorings) of Li<sub>2</sub>B<sub>3</sub>C and Li<sub>3</sub>B<sub>4</sub>C<sub>2</sub>, which are characterized by a distinctive pattern of alternating B-B and B-C zigzag chains. Surprisingly, the optimal configuration of Li<sub>2</sub>B<sub>3</sub>C exhibits an extremely low superconducting transition temperature of <i>T</i><sub><i>c</i></sub>&#xa0;&lt;&#xa0;0.03 K, which is attributed to the suppression of deformation potentials near the Fermi level caused by the specific electron filling of B-B zigzag chains. However, the <i>σ</i>-bonding electrons at the Fermi level are highly sensitive to external strain or pressure. Specifically, applying a&#xa0;−5% compressive uniaxial strain can significantly enhance the electron-phonon coupling and the Eliashberg spectral function, boosting up <i>T</i><sub><i>c</i></sub> to 37 K. This work not only presents a strategy for achieving high critical temperatures in Li<sub>n</sub>B<sub>n+1</sub>C<sub>n+1</sub> compounds, but also provides valuable insights into the complex interplay between electronic structure and superconducting interaction.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Optimal coloring and strain-enhanced superconductivity in LinBn+1Cn−1

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年2月10日

查看全文
  • Yuhao Gu,
  • Jiangping Hu,
  • Hong Jiang,
  • Tao Xiang

摘要

Boron-rich lithium borocarbides are promising candidates for phonon-mediated high-temperature superconductors due to their metallic σ-bonding electrons. Here, we use the cluster expansion method to identify energetically stable configurations (colorings) of Li2B3C and Li3B4C2, which are characterized by a distinctive pattern of alternating B-B and B-C zigzag chains. Surprisingly, the optimal configuration of Li2B3C exhibits an extremely low superconducting transition temperature of Tc < 0.03 K, which is attributed to the suppression of deformation potentials near the Fermi level caused by the specific electron filling of B-B zigzag chains. However, the σ-bonding electrons at the Fermi level are highly sensitive to external strain or pressure. Specifically, applying a −5% compressive uniaxial strain can significantly enhance the electron-phonon coupling and the Eliashberg spectral function, boosting up Tc to 37 K. This work not only presents a strategy for achieving high critical temperatures in LinBn+1Cn+1 compounds, but also provides valuable insights into the complex interplay between electronic structure and superconducting interaction.