We study the temperature dependence of the magnetic penetration depth in a 3D topological superconductor (TSC), incorporating the paramagnetic current due to the surface states. A TSC is predicted to host a gapless 2D surface Majorana fluid. In addition to the bulk-dominated London response, we identify a $T^3$ power-law-in-temperature contribution from the surface, valid in the low-temperature limit. Our system is fully gapped in the bulk, and should be compared to bulk nodal superconductivity, which also exhibits power-law behavior. Power-law temperature dependence of the penetration depth can be one indicator of topological superconductivity.

中文翻译：

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表面状态对拓扑超导体中穿透深度的幂律温度依赖性

我们研究了3D拓扑超导体（TSC）中磁渗透深度的温度依赖性，并结合了由于表面状态而产生的顺磁电流。预计TSC将容纳无间隙2D表面Majorana流体。除了以伦敦为主的答复外，我们还确定了${Ť}^3$表面的幂律温度贡献，在低温极限中有效。我们的系统在体积上有很大的空隙，应该与体积节点超导性进行比较，后者也表现出幂律特性。穿透深度的幂律温度依赖性可能是拓扑超导性的指标。