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Hole depletion and localization due to disorder in insulating PrBa2Cu3O7-d: a Compton scattering study

Abhay Shukla·Bernardo Barbiellini·Andreas Erb·Alfred A. Manuel·Thomas Buslaps·Veijo Honkimaki·Pekka Suortti
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Abstract

The (mostly) insulating behaviour of PrBa2Cu3O7-d is still unexplained and even more interesting since the occasional appearance of superconductivity in this material. Since YBa2Cu3O7-d is nominally iso-structural and always superconducting, we have measured the electron momentum density in these materials. We find that they differ in a striking way, the wavefunction coherence length in PrBa2Cu3O7-d 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 90K superconducting PrBa2Cu3O7-d crystallites.

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Abhay Shukla, Bernardo Barbiellini, Andreas Erb, Alfred A. Manuel, Thomas Buslaps, Veijo Honkimaki, Pekka Suortti. 1998-10-06. Hole depletion and localization due to disorder in insulating PrBa2Cu3O7-d: a Compton scattering study. https://doi.org/10.1103/physrevb.59.12127

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