Seminar: Holographic model of a doped Mott insulator

We are glad to announce that a lecture given by our distinguished guest Alexander Krikun (Leiden University) will be held this Wednesday.

Address – Skolkovo Institute of Science and Technology, Nobelya St., building 3,  room 407
Date – March 21, 2018.
Time – 16.30

Mott insulators are well known systems in condensed matter physics. If the normal state of the system is a Fermi liquid, characterized by the well defined quasiparticles, the Mott insulator formed at half filling on top of strong enough background lattice can be qualitatively understood as a “traffic jam” of these repulsive quasi-electrons. Doping of this system gives rise to the charged discommensurations, whose number is proportional to the number of dopants.

But what if the normal state is instead the densely entangled strange metal, where quasipaticles are not identifiable anymore? Then one gets the most notorious Mott insulator, observed in under-doped cuprate high-Tc superconductors. This state violates some of the simple logic which follows from classical “traffic jam” picture. For instance it has a stability regions, where the period discommensurations is unrelated to the doping (4a CDW).
The holographic duality, discovered in string theory, describes generic properties of certain classes of such densely entangled quantum matter. Using holography, one can build the “strange metal” version of the Mott insulator as a commensurate state between spontaneous intertwined charge density wave and a lattice. I will show that this state shares many properties with the conventional Mott insulator, but is different in several aspects. Crucially, these differences can shed light on the unconventional features of the doped Mott state in the under-doped cuprate.

Based on: arXiv:1710.05791