Mott transition

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

Nonequilibrium Density Of States And Distribution Functions For Strongly Correlated Materials Across The Mott Transition

Abstract: We examine the local density of states and the momentum-dependent distribution functions as they evolve in time for systems described by the FalicovKimball model initially in equilibrium, and then driven by a large uniform electric field turned on at time t = 0. We use exact dynamical mean-field theory, extended to nonequilibrium situations, to solve the problem. We focus on the accuracy of the numerics and on the interesting new features brought about by the strong correlations.

Superconductivity of InN caused by In‐In nano‐structure

Abstract: There is an optimum carrier density for the occurrence of the superconductivity in n-type InN. The lowest carrier density is limited by the Mott transition of ne ∼ 2 × 1017 cm–3 and the highest density is limited by the superconductivity to metal transition of ne ∼ 5 × 1020 cm–3. Between these carrier densities, InN shows superconductivity and vortex motion is a current tunneling through micro Josephson-junctions. A mechanism is proposed where the occurrence of the superconductivity is related to the presence of two u -parameters of 3/8 and 5/8, which causes In-In chains of finite length in the ab plane. The In-In chains, which originate from the In-In nano-structure elongating along [110], are coupled to form micro Josephsonjunctions. A possibility of nano-structure instability is suggested by the temperature dependence of the u -parameter obtained by molecular dynamics calculations. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Dimensional crossover and deconfinement in Bechgaard salts

Abstract: The Bechgaard salts are made of weakly coupled one dimensional chains. This particular structure gives the possibility to observe in these systems a dimensional crossover between a high temperature (or high energy) one dimensional phase and a two or three dimensional system. Since the filling of the chains is commensurate the system thus undergoes a deconfinement transition from a one dimensional Mott insulator to a two (or three) dimensional metal. Such a transition has of course a strong impact on the physical properties of these compounds, and is directly seen in transport measurements. In order to describe such a transition a dynamical mean field method has been introduced (chain-DMFT). Using this method we investigate a system Of Coupled Hubbard chains and show that we call indeed reproduce the deconfinement transition. This allows to determine physical quantities such as the transport transverse to the chains and the shape of the Fermi surface and quasiparticle residues in the low temperature phase.

Phase diagram and quasiparticle properties of the Hubbard model within cluster two-site dynamical mean-field theory

Abstract: We present a cluster dynamical mean-field treatment of the Hubbard model on a square lattice to study the evolution of magnetism and quasiparticle properties as the electron filling and interaction strength are varied Our approach for solving the dynamical mean-field equations is an extension of Potthoff's ``two-site'' method [Phys Rev B 64, 165114 (2001)], where the self-consistent bath is represented by a highly restricted set of states As well as the expected antiferromagnetism close to half-filling, we observe distortions of the Fermi surface The proximity of a van Hove point and the incipient antiferromagnetism lead to the evolution from an electronlike Fermi surface away from the Mott transition, to a holelike one near half-filling Our results also show a gap opening anisotropically around the Fermi surface, close to the Mott transition (reminiscent of the pseudogap phenomenon seen in the cuprate high-${T}_{c}$ superconductors) This leaves Fermi arcs that are closed into pockets by lines with very small quasiparticle residue

Finite-entanglement properties in the matrix product states of the one-dimensional Hubbard model

Abstract: We study the effects of limited entanglement in the one-dimensional Hubbard model by representing the ground states in the form of matrix product states. Finite-entanglement scaling behavior over a wide range is observed at half-filling. The critical exponents characterizing the length scale in terms of the size of the matrices used are obtained, confirming the theoretical prediction that the values of the exponents are solely determined by the central charge. The entanglement spectrum shows that a global double degeneracy occurs in the ground states with a charge gap. We also find that the Mott transition, tuned by changing the chemical potential, always occurs through a first-order transition, and the metallic phase has a few conducting states, including the states with a mean-field nature close to the critical point, as expected in variational matrix product states with a finite amount of entanglement.