Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of Physics Condensed Matter

The influence of hopping on valence transitions in the Falicov-Kimball model

Pavol Farkašovský

Published Apr 10, 1995• 10 citations
Publisher

Abstract

We use strong-coupling perturbation theory and the extrapolation of small-cluster exact-diagonalization calculations to describe the ground-state properties and possible intermediate-valence transitions of the spinless Falicov-Kimball model with a generalized type of hopping. It is shown that, even for relatively small values of the interaction strength, the Falicov-Kimball model undergoes only a few (discrete) intermediate-valence transitions, and this result is demonstrated to be independent of finite-size effects.

DOI
10.1088/0953-8984/7/15/007

Related papers

Electronic phase transitions in the spinless falicov-kimball model with correlated hopping

Pavol Farkašovský, Štefan Gál

The extrapolation of small-cluster exact-diagonalization calculations is used to examine the influence of correlated hopping on valence and metal-insulator transitions in the one-dimensional Falicov-Kimball model. It is shown that in the half-filled band case the ground-state phase diagram as well as the picture of valence and metal-insulator transitions found for the conventional Falicov-Kimball model (without correlated hopping) are strongly changed when the correlated hopping term is added. The effect of correlated hopping is so strong that it can induce the insulator-metal transition. Outside half-filling correlated hopping stabilizes the segregated phase in the ground-state, however, the nature of the ground-state remains qualitatively unchanged.

Phase Transitions•Dec 1, 2001•5 citations

The influence of correlated hopping on valence and metal-insulator transitions in the Falicov-Kimball model

Pavol Farkašovský

The extrapolation of small-cluster exact-diagonalization calculations is used to examine the influence of correlated hopping on valence and metal-insulator transitions in the one-dimensional Falicov-Kimball model. It is shown that the ground-state phase diagram as well as the picture of valence and metal-insulator transitions found for the conventional Falicov-Kimball model (without correlated hopping) are strongly changed when the correlated hopping term is added. The effect of correlated hopping is so strong that it can induce the insulator-metal transition, even in the half-filled band case.

arXiv:cond-mat/9908094•Aug 6, 1999•0 citations

PHASE TRANSITIONS INDUCED BY CORRELATED HOPPING IN THE FALICOV–KIMBALL MODEL

Hana Čenčariková, Pavol Farkašovský

The extrapolation of finite-cluster calculations is used to examine ground-state properties of the one-dimensional Falicov–Kimball model with correlated hopping. It is shown that the correlated hopping strongly influences both the valence transitions and the conducting properties of the model and so it should not be neglected in the correct description of materials with correlated electrons. This is illustrated for two selected values of the Coulomb interaction that represent typical behavior of the model for small and intermediate (strong) interactions. In both cases the insulator–metal transitions (accompanied by continuous or discontinuous valence transitions) induced by correlated hopping are observed.

arXiv:cond-mat/0312479•International Journal of Modern Physics B•Jan 30, 2004•15 citations

THE SPINLESS FALICOV–KIMBALL MODEL AWAY FROM HALF-FILLING

Štefan Gál

The one-dimensional spinless Falicov–Kimball (FKM) model is studied in the strong coupling limit away from half-filling. The small-cluster exact-diagonalization calculations are employed to obtain valence transitions in the ground state and for finite temperatures. It is found that in the ground state, the model describes continuous valence transitions for small band-fillings and both continuous and discontinuous transitions near half-filling. At finite temperatures, only continuous valence transitions are obtained. The valence is integer at low temperatures for small band-fillings and in other cases, it takes only intermediate values.

Modern Physics Letters B•Jun 30, 1999•4 citations

The influence of correlated hopping on the ground‐state properties of the two‐dimensional Falicov–Kimball model

Hana Čenčariková, Pavol Farkašovský

Abstract The extrapolation of finite cluster calculations is used to study effects of correlated hopping on the ground‐state properties of the two‐dimensional Falicov–Kimball model (FKM). It is shown that the ground‐state phase diagram as well as the picture of valence transitions found for the conventional FKM (without correlated hopping) are strongly changed when the correlated hopping term is added. In particular, it is found that non‐zero values of correlated hopping stabilize a new type of spatial charge ordering, the axial stripes, for a wide range of model parameters. This result indicates that the competition between the kinetic energy, the on‐site Coulomb energy and the correlated hopping term can be an alternative mechanism leading to stripe formation in the strongly correlated electron systems. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

physica status solidi (b)•Jul 12, 2005•6 citations

Ground states of the spinless Falicov-Kimball model in the strong-coupling limit

Pavol Farkašovský, Ivan Batko

The authors have studied energetic and structural ground-state properties of the one-dimensional Falicov-Kimball model in the strong-coupling limit. Using standard perturbation theory they recover some results already obtained (the phase segregation at large interactions) and present some new results concerning the ground state, e.,g., the analytic expression for the boundary, below which the segregated configuration cannot be the ground state, and the phase diagram of the model calculated for special periodic (aperiodic) configurations of ions and for the case when the ion concentration goes to zero.

Journal of Physics Condensed Matter•Sep 20, 1993•8 citations
We use strong-coupling perturbation theory and the extrapolation of small-cluster exact-diagonalization calculations to describe the ground-state properties and possible intermediate-valence transitions of the spinless Falicov-Kimball model with a generalized type of hopping. It is shown that, even for relatively small values of the interaction strength, the Falicov-Kimball model undergoes only a few (discrete) intermediate-valence transitions, and this result is demonstrated to be independent of finite-size effects.
The extrapolation of small-cluster exact-diagonalization calculations is used to examine the influence of correlated hopping on valence and metal-insulator transitions in the one-dimensional Falicov-Kimball model. It is shown that in the half-filled band case the ground-state phase diagram as well as the picture of valence and metal-insulator transitions found for the conventional Falicov-Kimball model (without correlated hopping) are strongly changed when the correlated hopping term is added. The effect of correlated hopping is so strong that it can induce the insulator-metal transition. Outside half-filling correlated hopping stabilizes the segregated phase in the ground-state, however, the nature of the ground-state remains qualitatively unchanged.
The extrapolation of small-cluster exact-diagonalization calculations is used to examine the influence of correlated hopping on valence and metal-insulator transitions in the one-dimensional Falicov-Kimball model. It is shown that the ground-state phase diagram as well as the picture of valence and metal-insulator transitions found for the conventional Falicov-Kimball model (without correlated hopping) are strongly changed when the correlated hopping term is added. The effect of correlated hopping is so strong that it can induce the insulator-metal transition, even in the half-filled band case.
The extrapolation of finite-cluster calculations is used to examine ground-state properties of the one-dimensional Falicov–Kimball model with correlated hopping. It is shown that the correlated hopping strongly influences both the valence transitions and the conducting properties of the model and so it should not be neglected in the correct description of materials with correlated electrons. This is illustrated for two selected values of the Coulomb interaction that represent typical behavior of the model for small and intermediate (strong) interactions. In both cases the insulator–metal transitions (accompanied by continuous or discontinuous valence transitions) induced by correlated hopping are observed.
The one-dimensional spinless Falicov–Kimball (FKM) model is studied in the strong coupling limit away from half-filling. The small-cluster exact-diagonalization calculations are employed to obtain valence transitions in the ground state and for finite temperatures. It is found that in the ground state, the model describes continuous valence transitions for small band-fillings and both continuous and discontinuous transitions near half-filling. At finite temperatures, only continuous valence transitions are obtained. The valence is integer at low temperatures for small band-fillings and in other cases, it takes only intermediate values.
Abstract The extrapolation of finite cluster calculations is used to study effects of correlated hopping on the ground‐state properties of the two‐dimensional Falicov–Kimball model (FKM). It is shown that the ground‐state phase diagram as well as the picture of valence transitions found for the conventional FKM (without correlated hopping) are strongly changed when the correlated hopping term is added. In particular, it is found that non‐zero values of correlated hopping stabilize a new type of spatial charge ordering, the axial stripes, for a wide range of model parameters. This result indicates that the competition between the kinetic energy, the on‐site Coulomb energy and the correlated hopping term can be an alternative mechanism leading to stripe formation in the strongly correlated electron systems. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The authors have studied energetic and structural ground-state properties of the one-dimensional Falicov-Kimball model in the strong-coupling limit. Using standard perturbation theory they recover some results already obtained (the phase segregation at large interactions) and present some new results concerning the ground state, e.,g., the analytic expression for the boundary, below which the segregated configuration cannot be the ground state, and the phase diagram of the model calculated for special periodic (aperiodic) configurations of ions and for the case when the ion concentration goes to zero.