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Jeudi 21 Avril 2016 14h
Amphi Holweck, Esc C,
1ème etage
Electronic transport in quasi-2D super-metallic oxides
The delafossite oxides PdCoO2 and PdCrO2 have a very simple electronic
structure, including a Fermi surface that avoids crossing the Brillouin
Zone boundary. This makes them the two-dimensional equivalent of alkali
metals. The suppression of umklapp scattering events leads to very long
mean free paths and pronounced thermal anisotropy at low temperatures.
The separation of the conducting Pd planes by magnetic CrO2 layers leads
to small-gap reconstruction of the Fermi surface. The signature of this
reconstruction is most dramatic in the Nernst response. We examine how
far these materials can be used as an analogy for the cuprate
superconductors, invoking the similarity in Fermi surface evolution in
the presence of short-range order.