Anomalous criticality in the electrical resistivity of La2-xSrxCuO4.
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.
Cooper
R A
RA
H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS81TL, UK.
Wang
Y
Y
Vignolle
B
B
Lipscombe
O J
OJ
Hayden
S M
SM
Tanabe
Y
Y
Adachi
T
T
Koike
Y
Y
Nohara
M
M
Takagi
H
H
Proust
Cyril
C
Hussey
N E
NE