Mott transition

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

Two-particle Fermi liquid parameters at the Mott transition: Vertex divergences, Landau parameters, and incoherent response in dynamical mean-field theory

Abstract: We consider the interaction-driven Mott transition at zero temperature from the viewpoint of microscopic Fermi liquid theory. To this end, we derive an exact expression for the Landau parameters within the dynamical mean-field theory (DMFT) approximation to the single-band Hubbard model. At the Mott transition, the symmetric and the antisymmetric Landau parameters diverge. The vanishing compressibility at the Mott transition directly implies the divergence of the forward-scattering amplitude in the charge sector, which connects the proximity of the Mott phase to a tendency toward phase separation. We verify the expected behavior of the Landau parameters in a DMFT application to the Hubbard model on the triangular lattice at finite temperature. Exact conservation laws and the Ward identity are crucial to capture vertex divergences related to the Mott transition. We furthermore generalize Leggett's formula for the static susceptibility of the Fermi liquid to the static fermion-boson response function. In the charge sector, the limits of small transferred momentum and frequency of this response function commute at the Mott transition.

Optical properties for the Mott transition in VO2

Abstract: The relationship between the first-order metal-insulator transition (MIT) and the structural phase transition (SPT) in VO2 film is analyzed by dielectric function, optical conductivity, plasma energy, and electrical conductivity The MIT and SPT temperatures in VO2 films were approximately 68 and 75 °C, respectively, with an intermediate phase existing between 68 and 75 °C The optical and electrical results indicate that the first-order MIT in VO2 films is not driven by the SPT

NMR Study on Heavily Doped Silicon. II

Abstract: Spin echo spectra, Knight shift and spin-lattice relaxation time are measured on 31 P in silicon crystals with phosphorus concentrations ranging from 4.5×10 18 cm -3 to 9.6×10 19 cm -3 over a temperature region from 4.2 K to 0.4 K. The shift and width of 31 P line is atrributed to the inhomogeneous electron contact field. The results together with those of 29 Si (J. Phys. Soc. Japan 36 (1974) 1377) support the Mott transition mechanism of metal-non metal transition and allow to interpret various properties of the metallic samples in terms of an electron gas with correlation.

Transport in a classical model of a one-dimensional Mott insulator: Influence of conservation laws

Abstract: We study numerically how conservation laws affect the optical conductivity σ(ω) of a slightly doped one-dimensional Mott insulator. We investigate a regime where the average distance between charge excitations is large compared to their thermal de Broglie wavelength and a classical description is possible. Due to conservation laws, the dc conductivity is infinite and the Drude weight D is finite even at finite temperatures. Our numerical results test and confirm exact theoretical predictions for D both for integrable and non-integrable models. Small deviations from integrability induce slowly decaying modes and, consequently, low-frequency peaks in σ(ω), which can be described by a memory matrix approach.