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Entropic Origin of Pseudogap Physics and a Mott-Slater Transition in Cuprates.

ABSTRACT: We propose a new approach to understand the origin of the pseudogap in the cuprates, in terms of bosonic entropy. The near-simultaneous softening of a large number of different q-bosons yields an extended range of short-range order, wherein the growth of magnetic correlations with decreasing temperature T is anomalously slow. These entropic effects cause the spectral weight associated with the Van Hove singularity (VHS) to shift rapidly and nearly linearly toward half filling at higher T, consistent with a picture of the VHS driving the pseudogap transition at a temperature ~T*. As a byproduct, we develop an order-parameter classification scheme that predicts supertransitions between families of order parameters. As one example, we find that by tuning the hopping parameters, it is possible to drive the cuprates across a transition between Mott and Slater physics, where a spin-frustrated state emerges at the crossover.

SUBMITTER: Markiewicz RS

PROVIDER: S-EPMC5361159 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Entropic Origin of Pseudogap Physics and a Mott-Slater Transition in Cuprates.

Markiewicz R S RS Buda I G IG Mistark P P Lane C C Bansil A A

Scientific reports 20170322

We propose a new approach to understand the origin of the pseudogap in the cuprates, in terms of bosonic entropy. The near-simultaneous softening of a large number of different q-bosons yields an extended range of short-range order, wherein the growth of magnetic correlations with decreasing temperature T is anomalously slow. These entropic effects cause the spectral weight associated with the Van Hove singularity (VHS) to shift rapidly and nearly linearly toward half filling at higher T, consis ...[more]

PMID: 28327627

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