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arXiv · 1807.02489

Parity-mixing superconducting phase in the Rashba-Hubbard model and its topological properties from dynamical mean field theory

Xiancong Lu·David Sénéchal
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Abstract

We investigate parity-mixing superconductivity in the two-dimensional Hubbard model with Rashba spin-orbit coupling, using Cellular Dynamical Mean-Field Theory (CDMFT). A superconducting state with mixed singlet $d$-wave and triplet $p$-wave character is found in a wide range of doping. The singlet component decreases with the amplitude of the Rashba spin-orbit coupling, whereas the triplet component increases, but both disappear at about 20\% doping. The effect of a Zeeman field is also investigated; it tends to suppress both types of superconductivity, but induces nontrivial topological properties: the computed bulk Chern number is nonzero in the mixed superconductivity phase, at least in the underdoped region. A strong suppression of the excitation gap occurs slightly after optimal doping; this might be the sign of a topological transition within the superconducting dome.

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Xiancong Lu, David Sénéchal. 2018-07-06. Parity-mixing superconducting phase in the Rashba-Hubbard model and its topological properties from dynamical mean field theory. https://doi.org/10.1103/physrevb.98.245118

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