title: Inverse correlation between quasiparticle mass and T c in a cuprate high-T c superconductor.
abstract: Close to a zero-temperature transition between ordered and disordered electronic phases, quantum fluctuations can lead to a strong enhancement of electron mass and to the emergence of competing phases such as superconductivity. A correlation between the existence of such a quantum phase transition and superconductivity is quite well established in some heavy fermion and iron-based superconductors, and there have been suggestions that high-temperature superconductivity in copper-oxide materials (cuprates) may also be driven by the same mechanism. Close to optimal doping, where the superconducting transition temperature T c is maximal in cuprates, two different phases are known to compete with superconductivity: a poorly understood pseudogap phase and a charge-ordered phase. Recent experiments have shown a strong increase in quasiparticle mass m* in the cuprate YBa2Cu3O7-δ as optimal doping is approached, suggesting that quantum fluctuations of the charge-ordered phase may be responsible for the high-T c superconductivity. We have tested the robustness of this correlation between m* and T c by performing quantum oscillation studies on the stoichiometric compound YBa2Cu4O8 under hydrostatic pressure. In contrast to the results for YBa2Cu3O7-δ, we find that in YBa2Cu4O8, the mass decreases as T c increases under pressure. This inverse correlation between m* and T c suggests that quantum fluctuations of the charge order enhance m* but do not enhance T c.
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
authors.forename: Carsten
authors.identifier: 0000-0002-6205-9863
authors.initials: C
authors.lastname: Putzke
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
authors.forename: Liam
authors.initials: L
authors.lastname: Malone
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 31400 Toulouse, France.
authors.forename: Sven
authors.identifier: 0000-0003-0967-424X
authors.initials: S
authors.lastname: Badoux
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 31400 Toulouse, France.
authors.forename: Baptiste
authors.initials: B
authors.lastname: Vignolle
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 31400 Toulouse, France.
authors.forename: David
authors.identifier: 0000-0001-5640-4934
authors.initials: D
authors.lastname: Vignolles
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 31400 Toulouse, France.; AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, aleja Adama Mickiewicza 30, 30-059 Krakow, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Tabis
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
authors.forename: Philip
authors.initials: P
authors.lastname: Walmsley
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
authors.forename: Matthew
authors.initials: M
authors.lastname: Bird
authors.affiliation: High Field Magnet Laboratory (HFML-EMFL), Radboud University, Toernooiveld 7, 6525 ED Nijmegen, Netherlands.
authors.forename: Nigel E
authors.identifier: 0000-0001-9194-1604
authors.initials: NE
authors.lastname: Hussey
authors.affiliation: Laboratoire National des Champs Magnétiques Intenses, CNRS-INSA-UJF-UPS, 31400 Toulouse, France.
authors.forename: Cyril
authors.initials: C
authors.lastname: Proust
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
authors.forename: Antony
authors.initials: A
authors.lastname: Carrington
mesh_terms: D003300:Copper / Q000737:chemistry; D004583:Electrons; D060526:Magnetic Fields; D011312:Pressure; D000072176:Superconductivity; D013696:Temperature; D062125:Thermometry; D044366:Transition Temperature
chemical_list: D003300:Copper; C000520:cuprous oxide
keywords: Cuprate superconductors; high pressure; quantum oscillations