Cargando…

How pressure enhances the critical temperature of superconductivity in YBa(2)Cu(3)O(6+y)

High-temperature superconducting cuprates respond to doping with a dome-like dependence of their critical temperature (T(c)). But the family-specific maximum T(c) can be surpassed by application of pressure, a compelling observation known for decades. We investigate the phenomenon with high-pressure...

Descripción completa

Detalles Bibliográficos
Autores principales: Jurkutat, Michael, Kattinger, Carsten, Tsankov, Stefan, Reznicek, Richard, Erb, Andreas, Haase, Jürgen
Formato: Online Artículo Texto
Lenguaje:English
Publicado: National Academy of Sciences 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9926205/
https://www.ncbi.nlm.nih.gov/pubmed/36608293
http://dx.doi.org/10.1073/pnas.2215458120
Descripción
Sumario:High-temperature superconducting cuprates respond to doping with a dome-like dependence of their critical temperature (T(c)). But the family-specific maximum T(c) can be surpassed by application of pressure, a compelling observation known for decades. We investigate the phenomenon with high-pressure anvil cell NMR and measure the charge content at planar Cu and O, and with it the doping of the ubiquitous CuO(2) plane with atomic-scale resolution. We find that pressure increases the overall hole doping, as widely assumed, but when it enhances T(c) above what can be achieved by doping, pressure leads to a hole redistribution favoring planar O. This is similar to the observation that the family-specific maximum T(c) is higher for materials where the hole content at planar O is higher at the expense of that at planar Cu. The latter reflects dependence of the maximum T(c) on the Cu–O bond covalence and the charge-transfer gap. The results presented here indicate that the pressure-induced enhancement of the maximum T(c) points to the same mechanism.