论文标题
在EUO/KTAO3（110）界面上可调的二维超导性和自旋轨道耦合
Tunable two-dimensional superconductivity and spin-orbit coupling at the EuO/KTaO3(110) interface
论文作者
论文摘要
非常规的量子状态，最著名的是二维（2D）超导性，已经在氧化物异质结构的接口上实现，可以通过门电压有效调节它们（$ v_g $）。这里我们报告说，高质量EUO（111）薄膜和KTAO3（KTO）（KTO）（110）底物之间的界面显示了超导性，具有开始过渡温度$ t_c^{oteT} $ = 1.35 k。 过渡。通过应用$ v_g $，可以将$ t_c^{notset} $从〜1调谐到1.7 k；这样的增强可能与增强的自旋轨道能量$ε_{so} $ = $ \ hbar $ / $τ_{so} $相关，其中$τ_{so} $是旋转 - 轨道放松时间。基于上临界场（$ h_ {c2} $）和磁电导的$τ_{so} $的进一步分析揭示了EUO/KTO（110）界面上旋转轨道耦合（SOC）的复杂性质，其机制具有不同的机制主导了SOC效应对超级传导性和磁通率的影响的影响。我们的结果表明，SOC应该被视为确定氧化物界面上2D超导性的重要因素。
Unconventional quantum states, most notably the two-dimensional (2D) superconductivity, have been realized at the interfaces of oxide heterostructures where they can be effectively tuned by the gate voltage ($V_G$). Here we report that the interface between high-quality EuO (111) thin film and KTaO3 (KTO) (110) substrate shows superconductivity with onset transition temperature $T_c^{onset}$ = 1.35 K. The 2D nature of superconductivity is verified by the large anisotropy of the upper critical field and the characteristics of a Berezinskii-Kosterlitz-Thouless transition. By applying $V_G$, $T_c^{onset}$ can be tuned from ~ 1 to 1.7 K; such an enhancement can be possibly associated with a boosted spin-orbit energy $ε_{so}$ = $\hbar$ / $τ_{so}$, where $τ_{so}$ is the spin-orbit relaxation time. Further analysis of $τ_{so}$ based on the upper critical field ($H_{c2}$) and magnetoconductance reveals complex nature of spin-orbit coupling (SOC) at the EuO/KTO(110) interface with different mechanisms dominate the influence of SOC effects for the superconductivity and the magnetotransport in the normal state. Our results demonstrate that the SOC should be considered as an important factor determining the 2D superconductivity at oxide interfaces.
