Novel antiferromagnetic quantum phase transition in underdoped cuprates

Hyok-Jon Kwon

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arXiv · cond-mat/9901208

Novel antiferromagnetic quantum phase transition in underdoped cuprates

Hyok-Jon Kwon

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Abstract

We investigate a zero-temperature itinerant antiferromagnetic transition where the fermions possess a d-wave gap. This problem pertains to both the nodal liquid insulating phase and the d-wave superconducting phase of the underdoped cuprates. We find that a non-trivial quantum phase transition exists, and that the quantum critical point is dominated by a long-ranged interaction ($|x-y|^{-2d}$) of the Néel order parameter, which is induced by the Dirac-like fermions near gap nodes. We formulate a Ginzburg-Landau functional and estimate the critical exponents via the large-N expansion method.

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Hyok-Jon Kwon. 1999-02-16. Novel antiferromagnetic quantum phase transition in underdoped cuprates. https://arxiv.org/abs/cond-mat/9901208

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