Topological phases due to the coexistence of superconductivity and spin-density wave: Application to high Tc superconductors in the underdoped regime

Amit Gupta; Debanand Sa

doi:10.1016/j.ssc.2014.11.014

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arXiv · 1401.0617

Topological phases due to the coexistence of superconductivity and spin-density wave: Application to high Tc superconductors in the underdoped regime

Amit Gupta·Debanand Sa

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Abstract

We consider the coexistence of superconductivity(SC) and spin-density wave(SDW). The SC is presumed to be of $d_{x^2-y^2}+id_{xy} (d_1 + i d_2) $ type whereas the SDW order parameter is of $BCS$/$d_{x y} $ symmetry. The Hamiltonian having such a structure is shown to have topological coexistence phases in addition to the conventional one. It is shown that the amplitudes of both the order parameters determine the nature of topological phases. A phase diagram characterizing different topological phases with their Chern numbers are obtained. The experimental realization of such topological phases with reference to high temperature superconductors in the extreme underdoped regime are discussed.

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Amit Gupta, Debanand Sa. 2014-01-03. Topological phases due to the coexistence of superconductivity and spin-density wave: Application to high Tc superconductors in the underdoped regime. https://doi.org/10.1016/j.ssc.2014.11.014

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