Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3

Liang Fu

doi:10.1103/physrevb.90.100509

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arXiv · 1408.6508

Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3

Liang Fu

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Abstract

CuxBi2Se3 was recently proposed as a promising candidate for time-reversal-invariant topological superconductors[1]. In this work, we argue that the unusual anisotropy of the Knight shift observed by Zheng[2], taken together with specific heat measurements, provides strong support for an unconventional odd-parity pairing in the two-dimensional E_u representation of the D3d crystal point group[1], which spontaneously breaks the three-fold rotational symmetry of the crystal, leading to a subsidiary nematic order. We predict that the spin-orbit interaction associated with hexagonal warping plays a crucial role in pinning the two-component order parameter and makes the superconducting state fully-gapped, leading to a topological superconductor. Experimental signatures of the E_u pairing related to the nematic order are discussed.

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Liang Fu. 2014-08-27. Odd-parity topological superconductor with nematic order: Application to CuxBi2Se3. https://doi.org/10.1103/physrevb.90.100509

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