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O(4)-Invariant Formulation of the Nodal Liquid

Chetan Nayak
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Abstract

We consider the O(4) symmetric point in the phase diagram of an electron system in which there is a transition between d_{x^2 - y^2} density-wave order and d_{x^2 - y^2} superconductivity. If the pseudospin $SU(2)\subset O(4)$ symmetry is disordered by quantum fluctuations, the Nodal Liquid can result. In this context, we (1) construct a pseudospin $σ$-model; (2) discuss its topological excitations; (3) point out the possibility of a {\it pseudospin-Peierls} state and (4) propose a phase diagram for the underdoped cuprate superconductors.

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Chetan Nayak. 2000-01-29. O(4)-Invariant Formulation of the Nodal Liquid. https://doi.org/10.1103/physrevb.62.r6135

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