ROLE OF THE OXYGEN CONTENT IN TLBA1.2LA0.8CUO5+DELTA SUPERCONDUCTORS

摘要

The electronic energy band structures of the La-doped superconductors TlBa1.2La0.8CuO5 + delta were calculated. The effect of the oxygen content on their electronic structures was studied. The results show that compared with those for TlBa2CuO5, the La doping at the Ba site results in the moderate change in the band structures and the decrease in the densities of states, but the increase in the oxygen content caused by the La doping results in the great change in the band structures and the densities of states near the Fermi surface. The low oxygen content causes the degree of complexity of the band structures and the densities of states near the Fermi level E(f) to increase and the high oxygen content causes them to decrease. The oxygen content plays a dominant role in TlBa1.2La0.8CuO5 + delta. In addition, the Cu-O planes are most sensitive to the increase in the oxygen content. (C) 1996 John Wiley & Sons, Inc. [References: 14]