Competing orders suppressed by disorder around a hidden quantum critical point in high-T c cuprate superconductors
SANNA, SAMUELE;RIGOLDI, AMERICO;CONCAS, GIORGIO;
2010-01-01
Abstract
We report extensive muon-spin-rotation measurements on the lightly doped Y1-xCaxBa2Cu3O6+y compound, which allows us to disentangle the effect of disorder, controlled by random Ca2+ substitution, from that of mere doping. A three-dimensional phase diagram of lightly doped cuprates is accurately drawn. It shows a quantum critical point around which a thermally activated antiferromagnetic phase competes with superconductivity. Disorder suppresses both the competing order parameters and the quantum critical point, unveiling an underlying frozen state.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.