Quantum Confinement Transition and Cuprate Criticality

T. Senthil; Matthew P. A. Fisher

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arXiv · cond-mat/9912380

Quantum Confinement Transition and Cuprate Criticality

T. Senthil·Matthew P. A. Fisher

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Abstract

Theoretical attempts to explain the origin of high temperature superconductivity are challenged by the complexity of the normal state, which exhibits three regimes with increasing hole doping: a pseudo-gap regime when underdoped, strange power laws near optimal doping and more conventional metallic behavior when heavily overdoped. We suggest that the origin of this behavior is linked to a zero temperature quantum phase transition separating the overdoped Fermi liquid from a spin-charge separated underdoped phase. Central to our analysis is a new $Z_2$ gauge theory formulation, which supports topological vortex excitations - dubbed visons. The visons are gapped in the underdoped phase, splitting the electron's charge and Fermi statistics into two separate excitations. Superconductivity occurs when the resulting charge $e$ boson condenses. The visons are condensed in the overdoped phase, thereby confining the charge and statistics of the electron leading to a Fermi liquid phase. Right at the quantum confinement transition the visons are in a critical state, leading to power law behavior for both charge and spin.

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T. Senthil, Matthew P. A. Fisher. 1999-12-21. Quantum Confinement Transition and Cuprate Criticality. https://arxiv.org/abs/cond-mat/9912380

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