论文标题
基于KTAO3的二维电子气体的超流体刚度
Superfluid stiffness of a KTaO3-based two-dimensional electron gas
论文作者
论文摘要
经过将近二十年的著名Laalo3/SRTIO3系统的剧烈工作后，最近发现了（111）基于面向的KTAO3的异质结构在氧化物接口领域的新动量，在（111）基于面向的KTAO3的异质结构中发现了超导二维电子气体（2-DEG）。但是，尽管两个接口具有共同的属性，但实验也表明了两个系统之间的重要差异。在这里，我们通过简单的薄层溅射在A（111）面向的KTAO3晶体的表面生成的2度高电导率。我们使用微波传输来表明（111）-KTAO3 2-DEGS在简单的BCS弱耦合极限模型中显示出无节点的超导级参数，其间隙值明显大于预期。与超导性的二维性质一致，我们证明了明确定义的berezinsky-kosterlitz-无尽的过渡类型，这尚未在基于SRTIO3的界面上报告。我们的发现为基础科学提供了创新的观点，也为诸如旋转轨道和拓扑电子等各个领域的设备应用提供了创新的观点。
After almost twenty years of intense work on the celebrated LaAlO3/SrTiO3 system, the recent discovery of a superconducting two-dimensional electron gases (2-DEG) in (111)-oriented KTaO3-based heterostructures injects new momentum to the field of oxides interfaces. However, while both interfaces share common properties, experiments also suggest important differences between the two systems. Here, we report gate tunable superconductivity in 2-DEGs generated at the surface of a (111)-oriented KTaO3 crystal by the simple sputtering of a thin Al layer. We use microwave transport to show that (111)-KTaO3 2-DEGs exhibit a node-less superconducting order parameter with a gap value significantly larger than expected within a simple BCS weak-coupling limit model. Consistent with the two-dimensional nature of superconductivity, we evidence a well-defined Berezinsky-Kosterlitz-Thouless type of transition, which was not reported on SrTiO3-based interfaces. Our finding offers innovative perspectives for fundamental science but also for device applications in a variety of fields such as spin-orbitronics and topological electronics.
