Dr. Roland Willa
We discuss the honeycomb pnictide superconductor SrPtAs . There is the intrinsic spin-orbit coupling in the non-interacting Hamiltonian due to the local lack of inversion centers in the conducting layers . In the superconducting state, the spontaneous magnetization has been observed by the muon spin relaxation measurement . The plausible candidate of the pairing symmetry is the chiral d-wave [4,5], which is the topological superconducting state with time-reversal-symmetry breaking supporting the chiral edge state at the sample boundary. We show that the boundary state causes the spontaneous spin polarization due to the spin-orbit coupling .
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