Electronic structure of PrBa2Cu3O7 and YBa2Cu3O7: A local spin density approximation with the on-site Coulomb interaction study

Abstract

Using the self-consistent linear muffin-tin orbitals and the atomic sphere approximation method, the band structure calculations for PrBa2Cu3O7 and YBa2Cu3O7 are performed in the regime of the local spin density approximation with the on-site Coulomb interaction (LSDA+U). The strong electron-electron correlation effects are considered for both the Pr 4f and Cu 3d states. Comparing with the LSDA calculations, the LSDA+U calculations show that, while the essential feature of energy band of YBa2Cu3O7 is preserved, the electronic structure of PrBa2Cu3O7 is quite different. For the bands arisen from the CuO2 planes, a gap with a value of 0.5 eV is opened, indicating the insulating or semiconducting character of the CuO2 planes. The pdσ bands associated with the CuO chains are across the Fermi level, revealing the metallic character of the CuO chains.