Schedule Nov 18, 2002
Band-structures of hole-doped cuprates and correlation with Tc max
Eva Pavarini, A. Volta
We have calculated and analyzed the bare conduction bands in many families of hole-doped high temperature superconductors.

By using a new downfolding procedure based on the density functional theory and the muffin-tin-orbital method, we have derived a simple, generic conduction band Hamiltonian for these systems. We have shown that the essential material dependence is contained in only one parameter, namely r=t'/t, the range of the hopping integrals in the CuO2 layer. This range parameter is controlled by the energy of the so called axial orbital, a hybrid between Cu 4s, Cu 3d x^2-y^2, Cu 3d 3z^2-1, apical O 2pz, and farther orbitals such as La 5d 3z^2-1.

We observe that the materials with higher Tc max have larger hopping ranges and axial orbitals more localized in the CuO2 layers. Possible reasons for this correlation will be mentioned.

Audio requires RealPlayer by RealNetworks.
Begin WebCam and audio for the whole talk: high bandwidth or medium bandwidth.
Or, begin audio only for the whole talk: high bandwidth or low bandwidth. (Or, right-click to download the whole audio file.)

To begin viewing slides, click on the first slide below. (Or, view as pdf.)

[01] [02] [03] [04] [05] [06] [07] [08] [09] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31]

Author entry (protected)