Hole depletion and localization due to disorder in insulating PrBa2Cu3O7−δ: A Compton scattering study
Year: 1999
Type: article
Abstract: The (mostly) insulating behavior of ${\mathrm{PrBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ is still unexplained and even more interesting due to the occasional appearance of superconductivity in this material. Since ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ is nominally isostructural and always superconducting, we have measured the electron momentum density in these materials. We find that they differ in a striking way, the wave function coherence length in ${\mathrm{PrBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ being strongly suppressed. We conclude that Pr on Ba-site substitution disorder is responsible for the metal-insulator transition. Preliminary efforts at growth with a method to prevent disorder yield 90 K superconducting ${\mathrm{PrBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ crystallites.
Institution: European Synchrotron Radiation Facility
Language: Latvian
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2093523671