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arXiv 0711.4154cond-mat.supr-con
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p波超导体中Skyrmion与涡旋磁通晶格的关系

Skyrmion versus vortex flux lattices in p-wave superconductors

Qi Li, John Toner, D. Belitz

摘要:

p波超导体除了在s波和p波材料中都可能存在的通常的涡旋之外,还允许称为Skyrmions的拓扑缺陷。在磁场中的强II型超导体中,Skyrmion磁通晶格产生的自由能低于Abrikosov磁通晶格的涡旋,因此应该在p波超导体中实现。我们解析计算了每skyrmion的能量,这与数值计算结果吻合得很好。由此,我们得到了作为外部磁场H的函数的磁感应强度B,以及在低临界场H_c 1附近的skyrmion晶格的弹性常数。与林德曼准则一起,这些结果足以预测skyrmion晶格的熔化曲线。我们发现一个显着的差异,在熔融曲线的涡旋晶格和skyrmion晶格:而前者是在所有温度下分离的迈斯纳相的涡旋液相,skyrmion晶格相共享一个直接的边界与迈斯纳相。也就是说,skyrmions晶格永远不会在Hc1附近熔化,而涡旋晶格总是在足够接近Hc1的地方熔化。这使得一个非常简单的测试是否存在一个skyrmion晶格。可能的muSR实验检测skyrmion晶格进行了讨论。

英文摘要:

p-wave superconductors allow for topological defects known as skyrmions, in addition to the usual vortices that are possible in both s-wave and p-wave materials. In strongly type-II superconductors in a magnetic field, a skyrmion flux lattice yields a lower free energy than the Abrikosov flux lattice of vortices, and should thus be realized in p-wave superconductors. We analytically calculate the energy per skyrmion, which agrees very well with numerical results. From this, we obtain the magnetic induction B as a function of the external magnetic field H, and the elastic constants of the skyrmion lattice, near the lower critical field H_c1. Together with the Lindemann criterion, these results suffice to predict the melting curve of the skyrmion lattice. We find a striking difference in the melting curves of vortex lattices and skyrmion lattices: while the former is separated at all temperatures from the Meissner phase by a vortex liquid phase, the skyrmion lattice phase shares a direct boundary with the Meissner phase. That is, skyrmions lattices never melt near Hc1, while vortex lattices always melt sufficiently close to Hc1. This allows for a very simple test for the existence of a skyrmion lattice. Possible muSR experiments to detect skyrmion lattices are also discussed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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