Possibility of chiral d-wave pairing in a honeycomb pnictide superconductor SrPtAs

TKM Institutsseminar


Jun Goryo


01/07/2021 14:00




Hirosaki University


Dr. Roland Willa


We discuss the honeycomb pnictide superconductor SrPtAs [1]. There is the intrinsic spin-orbit coupling in the non-interacting Hamiltonian due to the local lack of inversion centers in the conducting layers [2]. In the superconducting state, the spontaneous magnetization has been observed by the muon spin relaxation measurement [3]. 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 [6].

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[3] P. K. Biswas, et al, Phys. Rev. B 87, 180503(R) (2013).
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[6] J. Goryo, Y. Imai, W. B. Rui, M. Sigrist, and A. P. Schnyder, Phys. Rev. B 96, 140502(R) (2017).