جوابهاي خودسازگار ساختار الكتروني PrBa2Cu3O7با LSDA+U

Electronic structure of PrBa2Cu307 within LSDA+U: Different self-consistent solutions

Based on the density functional theory and using the full-potential linearized augmented-plane-waves method the electronic structure of PrBa2Cu307 (Prl23) system was calculated. The rotationally invariant local spin density approximation plus Hubbard parameter U was employed for Pr(4f) orbitals. One self-consistent solution more stable than the previous solution, which has been proposed by Liechtenstein and Mazin (LM), was found. In contrast to the LM solution, it can explain the results of the 170 NMR spectroscopy study of nonsuperconducting Prl23 samples. This new solution favors the suggestion that the pure Prl23 samples should be intrinsically superconductor and metal similar to the other RBa2Cu307 (R=Y or a rare earth element) samples. The imperfections cause the superconducting holes are transferred to the nonsuperconducting hole states around the high-symmetry (P/a, P/b, kz) line in the Brillouin zone and so, superconductivity is suppressed in the conventional samples. It predicts that the superconducting 2pa holes in the 02 sites of nonsuperconducting Prl23 samples should be depleted and the ones in the 03 sites should be almost unchanged.