Scholarlink

<p>In two dimensions, a phase-coherent superconducting state is established via a Berezinskii-Kosterlitz-Thouless (BKT) transition, whose critical temperature <i>T</i><sub>BKT</sub> is determined by the global superfluid stiffness in uniform superconducting systems. We report that at the interface between (111)-oriented KTaO<sub>3</sub> and ferromagnetic EuO, the two-dimensional superconducting state exhibits a BKT transition relying on the direction of in-plane bias current. The highest <i>T</i><sub>BKT</sub> occurs when current is applied along one of the [11<InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(\bar{2}\)</EquationSource> <EquationSource Format="MATHML"><math> <mover accent="true"> <mrow> <mn>2</mn> </mrow> <mo>¯</mo> </mover> </math></EquationSource> </InlineEquation>] axes of KTaO<sub>3</sub>, underscoring a spontaneous breaking of the threefold lattice rotational symmetry. Such directional dependence of <i>T</i><sub>BKT</sub> is consistently reflected in the nonreciprocal signals stemming from superconducting fluctuations above the transition. We attribute this phenomenon to an interfacial phase segregation; the phase with higher <i>T</i><sub>BKT</sub> self-organizes into quasi-one-dimensional textures that stretch along one of the [11<InlineEquation ID="IEq2"> <EquationSource Format="TEX">\(\bar{2}\)</EquationSource> <EquationSource Format="MATHML"><math> <mover accent="true"> <mrow> <mn>2</mn> </mrow> <mo>¯</mo> </mover> </math></EquationSource> </InlineEquation>] directions. Our results point toward the emergence of exotic phases of matter beyond the description of conventional BKT physics at a superconducting interface that is subjected to ferromagnetic proximity.</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

Directional-dependent Berezinskii–Kosterlitz–Thouless transition at EuO/KTaO3(111) interfaces

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月16日

查看全文
  • Zongyao Huang,
  • Zhengjie Wang,
  • Xiangyu Hua,
  • Huiyu Wang,
  • Zhaohang Li,
  • Shihao Liu,
  • Zhiwei Wang,
  • Feixiong Quan,
  • Zhen Wang,
  • Jing Tao,
  • James Jun He,
  • Ziji Xiang,
  • Xianhui Chen

摘要

In two dimensions, a phase-coherent superconducting state is established via a Berezinskii-Kosterlitz-Thouless (BKT) transition, whose critical temperature TBKT is determined by the global superfluid stiffness in uniform superconducting systems. We report that at the interface between (111)-oriented KTaO3 and ferromagnetic EuO, the two-dimensional superconducting state exhibits a BKT transition relying on the direction of in-plane bias current. The highest TBKT occurs when current is applied along one of the [11 \(\bar{2}\) 2 ¯ ] axes of KTaO3, underscoring a spontaneous breaking of the threefold lattice rotational symmetry. Such directional dependence of TBKT is consistently reflected in the nonreciprocal signals stemming from superconducting fluctuations above the transition. We attribute this phenomenon to an interfacial phase segregation; the phase with higher TBKT self-organizes into quasi-one-dimensional textures that stretch along one of the [11 \(\bar{2}\) 2 ¯ ] directions. Our results point toward the emergence of exotic phases of matter beyond the description of conventional BKT physics at a superconducting interface that is subjected to ferromagnetic proximity.