Talk by Bill Atkinson, Trent University, Canada – Niels Bohr Institute - University of Copenhagen

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Talk by Bill Atkinson, Trent University, Canada

Strongly-correlated materials have held the attention of the physics community for decades, first, because they lie outside the standard model of metals and insulators and, second, because they exhibit a range of new properties, such as high temperature superconductivity. Many of these materials have their electronic properties tuned by chemical doping, and there is a growing awareness that the disorder introduced by chemical doping can have important consequences. In this talk, I will focus on a recent prediction that a
novel zero bias anomaly (ZBA) should appear in the density of states.

A ZBA is a suppression of the density of states at the Fermi energy, due in this case to the simultaneous presence of disorder and interactions. I will explain why the ZBA is not expected on the basis of conventional Altshuler-Aronov theory, and then discuss our attempts to understand its underlying physics in strongly-correlated models. I will show that strong correlations lead to a new mechanism for suppressing the density of states at the Fermi level when disorder is present.