Evolution from a charge-ordered insulator to a high-temperature superconductor in Bi<sub>2</sub>Sr<sub>2</sub>(Ca,Dy)Cu<sub>2</sub>O<sub>8+δ</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39231956.
- Also identified by DOI 10.1038/s41467-024-52124-9 and PMC identifier 11375163.
- Licence recorded as CC BY-NC-ND.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
How Cooper pairs form and condense has been the main challenge in the physics of copper-oxide high-temperature superconductors. Great efforts have been made in the 'underdoped' region of the phase diagram, through doping a Mott insulator or cooling a strange metal. However, there is still no consensus on how superconductivity emerges when electron-electron correlations dominate and the Fermi surface is missing. To address this issue, here we carry out high-resolution resonant inelastic X-ray scattering and scanning tunneling microscopy studies on prototype cuprates Bi<sub>2</sub>Sr<sub>2</sub>Ca<sub>0.6</sub>Dy<sub>0.4</sub>Cu<sub>2</sub>O<sub>8+δ</sub> near the onset of superconductivity, combining bulk and surface, momentum- and real-space information. We show that an incipient charge order exists in the antiferromagnetic regime down to 0.04 holes per CuO<sub>2</sub> unit, entangled with a particle-hole asymmetric pseudogap. The charge order induces an intensity anomaly in the bond-buckling phonon branch, which exhibits an abrupt increase once the system enters the superconducting dome. Our results suggest that the Cooper pairs grow out of a charge-ordered insulating state, and then condense accompanied by an enhanced interplay between charge excitations and electron-phonon coupling.