论文标题
$ {4π} $的演变在存在面内磁场的情况下定期超电流
Evolution of ${4π}$-periodic Supercurrent in the Presence of In-plane Magnetic Field
论文作者
论文摘要
在存在4 $π$的周期性贡献的情况下，例如在拓扑约瑟夫森交界处，预计奇数夏皮罗步骤将缺失。虽然在几种物质系统中观察到缺少奇数的shapiro步骤，并在拓扑超导性的背景下进行了解释，但在拓扑上琐碎的连接中也观察到了它们。在这里，我们研究了在存在面内磁场$ b^θ$的情况下，在Al-Inas连接处这种微不足道的奇数shapiro步骤的演变。我们发现，奇数步骤在交叉$ b^θ$值下重新出现，该值表现出取决于自旋轨道耦合效应的平面内部角度各向异性。我们通过理论上分析了Andreev结合状态频谱以及由连接的非绝热动态引起的过渡来解释这种行为。我们的结果突出了缺少夏皮罗步骤的复杂现象学和旨在实现主要国家的平面约瑟夫森交界处的当前阶段关系。
In the presence of a 4$π$-periodic contribution to the current phase relation, for example in topological Josephson junctions, odd Shapiro steps are expected to be missing. While missing odd Shapiro steps have been observed in several material systems and interpreted in the context of topological superconductivity, they have also been observed in topologically trivial junctions. Here, we study the evolution of such trivial missing odd Shapiro steps in Al-InAs junctions in the presence of an in-plane magnetic field $B^θ$. We find that the odd steps reappear at a crossover $B^θ$ value, exhibiting an in-plane field angle anisotropy that depends on spin-orbit coupling effects. We interpret this behavior by theoretically analyzing the Andreev bound state spectrum and the transitions induced by the non-adiabatic dynamics of the junction. Our results highlight the complex phenomenology of missing Shapiro steps and the underlying current phase relations in planar Josephson junctions designed to realize Majorana states.
