Materials Science

Focus on quantum materials: KTaO3 two-dimensional interface superconductivity

  • YIN Xinmao ,
  • SUN Mengxia ,
  • NING Yuanjie ,
  • DAI Liang ,
  • LI Minjuan ,
  • CAI Chuanbing
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  • Shanghai Key Laboratory of High Temperature Superconductors, College of Sciences, Shanghai University, Shanghai 200444, China

Received date: 2024-03-11

  Online published: 2025-09-16

Abstract

The discovery of two-dimensional electron gas (2DEG) and interfacial superconductivity within perovskite oxide heterostructures has made them one of the research hotspots. In recent years, there have been groundbreaking advancements in the study of oxide interfaces. In addition to the conventional LaAlO$_{3}$/SrTiO$_{3}$ (LAO/STO) interface, superconductivity has been observed at the KTaO$_{3}$ (KTO) interface in 2021, with a superconducting transition temperature ($T_{\rm c}$) approximately an order of magnitude higher than that of LAO/STO, reaching around 2 K, sparking widespread attention. Compared to the STO interface system, the KTO oxide interface exhibits characteristics such as high carrier mobility and strong spin-orbit coupling (SOC), providing a new avenue for understanding the mechanism of unconventional superconductivity and studying new physical properties, thus establishing KTO heterostructures as promising candidates for future electronic and spintronic applications. This paper aims to summarize the latest progress in KTO interfaces over the past five years, provide an in-depth overview of the novel physical phenomena of superconductivity at the interfaces of various oxides and KTO, and discuss unresolved issues in current researches, thereby guiding the direction of future investigations.

Cite this article

YIN Xinmao , SUN Mengxia , NING Yuanjie , DAI Liang , LI Minjuan , CAI Chuanbing . Focus on quantum materials: KTaO3 two-dimensional interface superconductivity[J]. Journal of Shanghai University, 2025 , 31(4) : 591 -606 . DOI: 10.12066/j.issn.1007-2861.2582

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