Field-dependent specific heat of the canonical underdoped cuprate superconductor YBa 2 Cu 4 O 8
Authors
Tallon, Jeffery L.
Loram, John W.
Publication Date
2020-12-18Journal Title
Scientific Reports
Publisher
Nature Publishing Group UK
Volume
10
Issue
1
Language
en
Type
Article
This Version
VoR
Metadata
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Tallon, J. L., & Loram, J. W. (2020). Field-dependent specific heat of the canonical underdoped cuprate superconductor YBa 2 Cu 4 O 8. Scientific Reports, 10 (1)https://doi.org/10.1038/s41598-020-79017-3
Abstract
Abstract: The cuprate superconductor YBa2Cu4O8, in comparison with most other cuprates, has a stable stoichiometry, is largely free of defects and may be regarded as the canonical underdoped cuprate, displaying marked pseudogap behaviour and an associated distinct weakening of superconducting properties. This cuprate ‘pseudogap’ manifests as a partial gap in the electronic density of states at the Fermi level and is observed in most spectroscopic properties. After several decades of intensive study it is widely believed that the pseudogap closes, mean-field like, near a characteristic temperature, T∗, which rises with decreasing hole concentration, p. Here, we report extensive field-dependent electronic specific heat studies on YBa2Cu4O8 up to an unprecedented 400 K and show unequivocally that the pseudogap never closes, remaining open to at least 400 K where T∗ is typically presumed to be about 150 K. We show from the NMR Knight shift and the electronic entropy that the Wilson ratio is numerically consistent with a weakly-interacting Fermion system for the near-nodal states. And, from the field-dependent specific heat, we characterise the impact of fluctuations and impurity scattering on the thermodynamic properties.
Keywords
Article, /639/301, /639/766, article
Identifiers
s41598-020-79017-3, 79017
External DOI: https://doi.org/10.1038/s41598-020-79017-3
This record's URL: https://www.repository.cam.ac.uk/handle/1810/315448
Rights
Licence:
http://creativecommons.org/licenses/by/4.0/