Fermi-surface pockets in YBa2Cu3O6.5: Comparison of ab initio techniques
FILIPPETTI, ALESSIO;FIORENTINI, VINCENZO
2009-01-01
Abstract
We study the Fermi surface of metallic, nonmagnetic ortho-II YBa2Cu3O6.5 using three different density-functional-based band-structure techniques [generalized gradient approximation (GGA), GGA+U, and pseudo-self-interaction correction (PSIC)]. The calculated Fermi surface exhibits no pockets in GGA+U and PSIC, and a minor one in GGA. Upon shifting the Fermi level in the vicinity of the calculated value, we instead observe several pocket structures. We calculate their cross-sectional areas and cyclotron masses. Overall, our calculations show no solid evidence of the existence of electronlike-nor, in fact, of any-Fermi-surface pockets in this phase. This suggests that the origin of the pockets should be sought for in other different phases.Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.