Mott transition

About: Mott transition is a research topic. Over the lifetime, 2444 publications have been published within this topic receiving 78401 citations.

Fermi surface topology of Ca1.5Sr0.5RuO4 determined by angle-resolved photoelectron spectroscopy

Abstract: We report angle-resolved photoelectron spectroscopy results of the Fermi surface of Ca1.5Sr0.5RuO4, which is at the boundary of magnetic/orbital instability in the phase diagram of the Ca-substituted Sr ruthenates. Three t(2g) energy bands and the corresponding Fermi surface sheets are observed, which are also present in the Ca-free Sr2RuO4. We find that while the Fermi surface topology of the alpha,beta (d(yz,zx)) sheets remains almost the same in these two materials, the gamma (d(xy)) sheet exhibits a holelike Fermi surface in Ca1.5Sr0.5RuO4 in contrast to being electronlike in Sr2RuO4. Our observation of all three volume conserving Fermi surface sheets clearly demonstrates the absence of orbital-selective Mott transition, which was proposed theoretically to explain the unusual transport and magnetic properties in Ca1.5Sr0.5RuO4.

Cluster Dynamical Mean Field Theory

Abstract: Cluster dynamical mean-field theory is an extension of dynamical mean-field theory (DMFT) where the single-site impurity is replaced with a cluster of sites with open boundary conditions. Compared with single-site DMFT, this takes into account short-range correlations exactly and can probe the presence of broken-symmetry phases such as d-wave superconductivity and antiferromagnetism. This chapter reviews the basic CDMFT procedure, as well as issues related to the use of an exact diagonalization solver for the impurity problem. The QMC solvers are also briefly reviewed, as well as results on the Mott transition and on models for the cuprates.

Extremely correlated Fermi liquid theory meets dynamical mean-field theory: Analytical insights into the doping-driven Mott transition

Abstract: We consider a doped Mott insulator in the large dimensionality limit within both the recently developed extremely correlated Fermi liquid (ECFL) theory and the dynamical mean-field theory (DMFT). We show that the general structure of the ECFL sheds light on the rich frequency dependence of the DMFT self-energy. Using the leading Fermi liquid form of the two key auxiliary functions introduced in the ECFL theory, we obtain an analytical ansatz, which provides a good quantitative description of the DMFT self-energy down to hole doping level $\ensuremath{\delta}\ensuremath{\simeq}0.2$. In particular, the deviation from Fermi liquid behavior and the corresponding particle-hole asymmetry developing at a low-energy scale are well reproduced by this ansatz. The DMFT being exact at large dimensionality, our study also provides a benchmark of the ECFL in this limit. We find that the main features of the self-energy and spectral line shape are well reproduced by the ECFL calculations in the $O({\ensuremath{\lambda}}^{2})$ minimal scheme, for not too low doping level $\ensuremath{\delta}\ensuremath{\gtrsim}0.3$. The DMFT calculations reported here are performed using a state-of-the-art numerical renormalization-group impurity solver, which yields accurate results down to an unprecedentedly small doping level $\ensuremath{\delta}\ensuremath{\lesssim}0.001$.

Full‐configuration‐interaction study of the metal‐insulator transition in a model system: Hn linear chains n=4, 6,…, 16

Abstract: The metal-insulator transition induced by electron correlation (Mott transition) is studied with ab initio full CI methods in model systems. These are linear chains of equally spaced hydrogen atoms. Different indicators of the metal-insulator transition (maximum of the localization tensor or of the polarizability) areused and discussed. It is shown that the different indicators give concordant results, and that the transition is associated to a change in electron correlation, measured by the “particle-hole” symmetric correlation entropy. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111:3416–3423, 2011