Quantum critical point with competing propagating and diffusive spin excitations

Joerg Schmalian

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arXiv · cond-mat/9810041

Quantum critical point with competing propagating and diffusive spin excitations

Joerg Schmalian

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Abstract

Feedback effects due to spin fluctuation induced precursors in the fermionic quasiparticle spectrum are taken into account in the description of a quantum critical point of itinerant spin systems. A correlation length dependent spin damping occurs, leading to a dynamical scaling with z\approx 1 which non-trivially competes with the conventional spin wave behavior. We obtain, within a one loop renormalization group approach, a quantitative explanation for the scaling behavior seen in underdoped cuprate superconductors.

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Joerg Schmalian. 1998-10-05. Quantum critical point with competing propagating and diffusive spin excitations. https://arxiv.org/abs/cond-mat/9810041

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