Re-entrant charge order in overdoped (Bi,Pb)$_{2.12}$Sr$_{1.88}$CuO$_{6+\delta}$ outside the pseudogap regime

摘要

Charge modulations are considered as a leading competitor of high-temperaturesuperconductivity in the underdoped cuprates, and their relationship to Fermisurface reconstructions and to the pseudogap state is an important subject ofcurrent research. Overdoped cuprates, on the other hand, are widely regarded asconventional Fermi liquids without collective electronic order. For theoverdoped (Bi,Pb)2.12Sr1.88CuO6+{\delta} (Bi2201) high-temperaturesuperconductor, here we report resonant x-ray scattering measurements revealingincommensurate charge order reflections, with correlation lengths of 40-60lattice units, that persist up to at least 250K. Charge order is markedly morerobust in the overdoped than underdoped regime but the incommensurate wavevectors follow a common trend; moreover it coexists with a single,unreconstructed Fermi surface, without pseudogap or nesting features, asdetermined from angle-resolved photoemission spectroscopy. This re-entrantcharge order is reproduced by model calculations that consider a strong vanHove singularity within a Fermi liquid framework.