Day / Time
Date(s) - 18/11/2014
13 h 00 min - 14 h 00 min
Ecole de Physique, Auditoire Stueckelberg, 24 quai Ernest-Ansermet
Impact of pseudo-gap states on the pinning energy and irreversibility field of High Temperature Superconductors
School of Physics and Astronomy, Sackler Faculty of Exact Sciences Tel Aviv University, Tel Aviv 69867, Israel
The existence of pseudo-gap states at energies larger than the coherence energy scale is shown to be at the origin of the difficulties encountered in achieving strong vortex pinning in the high Tc cuprates. Reduction or elimination of the pseudo-gap states by overdoping is effective in increasing the condensation energy and the irreversibility field. In YBa2Cu3O7 a full BCS state, with a single energy scale, can be restored, leading to the highest known irreversibility field and pinning strength. In the bismuthates the detrimental effect of the pseudo-gap states can only be mitigated to some extent by overdoping.