title: Anomalous criticality in the electrical resistivity of La2-xSrxCuO4.
abstract: The presence or absence of a quantum critical point and its location in the phase diagram of high-temperature superconductors have been subjects of intense scrutiny. Clear evidence for quantum criticality, particularly in the transport properties, has proved elusive because the important low-temperature region is masked by the onset of superconductivity. We present measurements of the low-temperature in-plane resistivity of several highly doped La2-xSrxCuO4 single crystals in which the superconductivity had been stripped away by using high magnetic fields. In contrast to other quantum critical systems, the resistivity varies linearly with temperature over a wide doping range with a gradient that scales monotonically with the superconducting transition temperature. It is maximal at a critical doping level (pc) approximately 0.19 at which superconductivity is most robust. Moreover, its value at pc corresponds to the onset of quasi-particle incoherence along specific momentum directions, implying that the interaction that first promotes high-temperature superconductivity may ultimately destroy the very quasi-particle states involved in the superconducting pairing.
authors.affiliation: H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS81TL, UK.
authors.forename: R A
authors.initials: RA
authors.lastname: Cooper
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: B
authors.initials: B
authors.lastname: Vignolle
authors.forename: O J
authors.initials: OJ
authors.lastname: Lipscombe
authors.forename: S M
authors.initials: SM
authors.lastname: Hayden
authors.forename: Y
authors.initials: Y
authors.lastname: Tanabe
authors.forename: T
authors.initials: T
authors.lastname: Adachi
authors.forename: Y
authors.initials: Y
authors.lastname: Koike
authors.forename: M
authors.initials: M
authors.lastname: Nohara
authors.forename: H
authors.initials: H
authors.lastname: Takagi
authors.forename: Cyril
authors.initials: C
authors.lastname: Proust
authors.forename: N E
authors.initials: NE
authors.lastname: Hussey