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arXiv · 1111.5033

Pairing Glue Activation in Cuprates within the Quantum Critical Regime

Josef Ashkenazi·Neil F. Johnson
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Abstract

A grand challenge in many-body quantum physics is to explain the apparent connection between quantum criticality and high-temperature superconductivity in the cuprates and similar systems, such as the iron pnictides and chalcogenides. Here we argue that the quantum-critical regime plays an essential role in activating a strong-pairing mechanism: although pairing bosons create a symmetry-breaking instability which suppresses pairing, the combination of these broken-symmetry states within the critical regime can restore this symmetry for the paired quasiparticles. This condition is shown to be met within a large-U ansatz. A hidden quantum phase transition then arises between a Fermi-liquid and a non-Fermi-liquid broken-symmetry striped state, and a critical regime in which the broken-symmetry states are combined.

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Josef Ashkenazi, Neil F. Johnson. 2012-05-29. Pairing Glue Activation in Cuprates within the Quantum Critical Regime. https://doi.org/10.1209/0295-5075%2F98%2F47011

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