Scholarlink

<p>The observation of high-<i>T</i><sub>c</sub> superconductivity (HTSC) in concomitant with pressure-induced orthorhombic-tetragonal structural transition in bilayer La<sub>3</sub>Ni<sub>2</sub>O<sub>7</sub> has sparked hopes of achieving HTSC by stabilizing the tetragonal phase at ambient pressure. Chemical pressure, introduced by replacing La<sup>3+</sup> with smaller rare-earth <i>R</i><sup>3+</sup> has been considered as a potential route. However, our experimental and theoretical investigation reveals that such substitutions, despite causing lattice contraction, actually produce stronger orthorhombic distortions, requiring higher pressures for the structural transition. A linear extrapolation of <i>P</i><sub>c</sub> versus the average size of <i>A</i>-site cations (&lt;<i>r</i><sub><i>A</i></sub>&gt;), yields a putative critical value of &lt;<i>r</i><sub><i>A</i></sub>&gt;<sub>c</sub> ≈ 1.23 Å for <i>P</i><sub>c</sub> ≈ 1 bar. The negative correlation between <i>P</i><sub>c</sub> and &lt;<i>r</i><sub><i>A</i></sub>&gt; indicates that replacing La<sup>3+</sup> with smaller <i>R</i><sup>3+</sup> ions is unlikely to reduce <i>P</i><sub>c</sub> to ambient pressure. Instead, substituting La<sup>3+</sup> with larger cations like Sr<sup>2+</sup> or Ba<sup>2+</sup> might be a feasible approach. Our results provide guidance for realizing ambient-pressure HTSC in bilayer nickelates.</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

Chemical versus physical pressure effects on the structure transition of bilayer nickelates

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年1月2日

查看全文
  • Gang Wang,
  • Ningning Wang,
  • Tenglong Lu,
  • Stuart Calder,
  • Jiaqiang Yan,
  • Lifen Shi,
  • Jun Hou,
  • Liang Ma,
  • Lili Zhang,
  • Jianping Sun,
  • Bosen Wang,
  • Sheng Meng,
  • Miao Liu,
  • Jinguang Cheng

摘要

The observation of high-Tc superconductivity (HTSC) in concomitant with pressure-induced orthorhombic-tetragonal structural transition in bilayer La3Ni2O7 has sparked hopes of achieving HTSC by stabilizing the tetragonal phase at ambient pressure. Chemical pressure, introduced by replacing La3+ with smaller rare-earth R3+ has been considered as a potential route. However, our experimental and theoretical investigation reveals that such substitutions, despite causing lattice contraction, actually produce stronger orthorhombic distortions, requiring higher pressures for the structural transition. A linear extrapolation of Pc versus the average size of A-site cations (<rA>), yields a putative critical value of <rA>c ≈ 1.23 Å for Pc ≈ 1 bar. The negative correlation between Pc and <rA> indicates that replacing La3+ with smaller R3+ ions is unlikely to reduce Pc to ambient pressure. Instead, substituting La3+ with larger cations like Sr2+ or Ba2+ might be a feasible approach. Our results provide guidance for realizing ambient-pressure HTSC in bilayer nickelates.