论文标题
常规超导微桥的涡流限制临界电流的非核心
Non-reciprocity of Vortex-limited Critical Current in Conventional Superconducting Micro-bridges
论文作者
论文摘要
在多种超导系统中已经观察到临界电流中的非循环性，并被称为超导二极管效应。效果的根源取决于对称性破坏机制。我们研究了NBN和NBN/磁绝缘子（MI）杂种的超导微桥。当施加了较小至25毫升的平面磁场时，我们观察到$ \ $ 〜30 \％的巨大二极管效率。在NBN和NBN/MI杂种中，我们发现当磁场平行于样品平面时，二极管效应消失。我们的观察结果与由涡流表面屏障确定的临界电流一致。超导带的两个边缘上的不平等障碍会导致二极管效应。此外，观察到的纠正量最高为温度$ \ sim $ 10〜K，这使得基于二极管应用的设备在更大的温度范围内的设备可能比以前更大。
Non-reciprocity in the critical current has been observed in a variety of superconducting systems and has been called the superconducting diode effect. The origin underlying the effect depends on the symmetry breaking mechanisms at play. We investigate superconducting micro bridges of NbN and also NbN/magnetic insulator (MI) hybrids. We observe a large diode efficiency of $\approx$~30\% when an out-of-plane magnetic field as small as 25~mT is applied. In both NbN and NbN/MI hybrid, we find that the diode effect vanishes when the magnetic field is parallel to the sample plane. Our observations are consistent with the critical current being determined by the vortex surface barrier. Unequal barriers on the two edges of the superconductor strip result in the diode effect. Furthermore, the rectification is observed up to a temperature $\sim$10~K, which makes the device potential for diode based applications over larger temperature range than before.
