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arXiv · 1710.00719

Topologically protected Landau level in the vortex lattice of a Weyl superconductor

M. J. Pacholski·C. W. J. Beenakker·İ. Adagideli
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Abstract

The question whether the mixed phase of a gapless superconductor can support a Landau level is a celebrated problem in the context of \textit{d}-wave superconductivity, with a negative answer: The scattering of the subgap excitations (massless Dirac fermions) by the vortex lattice obscures the Landau level quantization. Here we show that the same question has a positive answer for a Weyl superconductor: The chirality of the Weyl fermions protects the zeroth Landau level by means of a topological index theorem. As a result, the heat conductance parallel to the magnetic field has the universal value $G=\tfrac{1}{2}g_0 \Phi/\Phi_0$, with $\Phi$ the magnetic flux through the system, $\Phi_0$ the superconducting flux quantum, and $g_0$ the thermal conductance quantum.

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M. J. Pacholski, C. W. J. Beenakker, İ. Adagideli. 2017-10-02. Topologically protected Landau level in the vortex lattice of a Weyl superconductor. https://doi.org/10.1103/physrevlett.121.037701

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