Transport with no quasiparticles: a view from the large N limit

by Prof. Erez Berg

Weizmann Institute Of Science

at Condensed Matter Seminar

Mon, 06 Jan 2020, 11:30
Sacta-Rashi Building for Physics (54), room 207

Abstract

One of the central open problems in the study of strongly
correlated electron systems is how to describe a metallic "liquid"
state of electrons beyond the conventional Fermi liquid paradigm of
metals. Such states seem ubiquitous in different materials, and are of
particular interest because they are the "parent" states of various
interesting electronic phases, such as high temperature
superconductors. Yet, their understanding is very poor, mostly due to
the lack of tractable models that can be used to describe them. In
this talk, I will describe a class of especially designed, tractable
models that give theoretically controlled access to non-quasiparticle
transport regimes. These models are solvable in the limit of a large
number of local degrees of freedom (electronic "orbitals" or phonon
modes). In the electron-phonon models, these models can describe both
resistivity saturation near the Mott-Ioffe-Regel limit or its absence,
depending on microscopics; in models with strong electron-electron
interactions, a crossover from a Fermi liquid to an incoherent metal
or a marginal Fermi liquid is obtained. We discuss the possible
implications of these results for strongly correlated metals and high
temperature superconductivity.

Created on 19-10-2019 by Meidan, Dganit (dganit)
Updaded on 02-01-2020 by Meidan, Dganit (dganit)