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Model simulation study of the structural stability of oxygen order in the YBa2Cu3O6+χ superconductor

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

A stability analysis is made of a model of the high-temperature superconductor YBa2Cu3O6+x by computer simulation of the oxygen ordering processes in the CuO-basal plane. The oxugen ordering is modelled within a two-dimensional lattice-gas model subject to varying external oxygen pressures and different annealing schedules. This model has previously proved successful in describing static as well as dynamic properties of the oxygen ordering processes. It is found that the domain formation and the stability of the oxygen-ordered orthorhombic phases (ortho-I and ortho-II) at low temperatures are crucially dependent on the temperature where the oxygen pressure is decreased, as well as the cooling rate employed in the annealing. For higher temperatures, the cooling rate and the initial oxygen content are less important. It is found that the size of the ortho-I domains, which is important for a high superconductivity transition temperature, is optimal when a high external oxygen pressure is maintained until low temperatures have been achieved.

OriginalsprogEngelsk
TidsskriftComputational Materials Science
Vol/bind1
Udgave nummer1
Sider (fra-til)25-32
Antal sider8
ISSN0927-0256
DOI
StatusUdgivet - 1992
Eksternt udgivetJa

ID: 236891941