Excitonic phase transition in the extended three-dimensional Falicov-Kimball model

Abstract

We study the excitonic phase transition in a system of the conduction band electrons and valence band holes described by the three-dimensional (3D) extended Falicov-Kimball (EFKM) model with the tunable Coulomb interaction $U$ between both species. By lowering the temperature, the electron-hole system may become unstable with respect to the formation of the excitons, i.e, electron-hole pairs at temperature $T=T_{\Delta }$, exhibiting a gap $\Delta$ in the particle excitation spectrum. To this end we implement the functional integral formulation of the EFKM, where the Coulomb interaction term is expressed in terms of U(1) phase variables conjugate to the local particle number, providing a useful representation of strongly correlated system. The effective action formalism allows us to formulate a problem in the phase-only action in the form of the quantum rotor model and to obtain analytical formula for the critical lines and other quantities of physical interest like charge gap, chemical potential and the correlation length.

27 pages, 15 figures (in the arXive version), 37 pages and 15 figures (in the published version)

References in corpus (10)

• Evidence for an excitonic insulator phase in 1T-TiSe${}_2$
• Orthorhombic-to-Monoclinic Phase Transition of Ta2NiSe5 Induced by the Bose-Einstein Condensation of Excitons
• On the possibility of an excitonic insulator at the semiconductor-semimetal transition
• Bound state formation and nature of the excitonic insulator phase in the extended Falicov-Kimball model
• Weak-coupling Treatment of Electronic (Anti-)Ferroelectricity in the Extended Falicov-Kimball Model
• Hartree-Fock study of electronic ferroelectricity in the Falicov-Kimball model with $f$-$f$ hopping
• Coherence and Optical Emission from Bilayer Exciton Condensates
• Excitonic BCS-BEC crossover at finite temperature: Effects of repulsion and electron-hole mass difference
• Critical charge instability on verge of the Mott transition and the origin of quantum protection in high-$T_c$ cuprates
• Generic gauge fields in the Hubbard model: emergence of pairing interaction

Cited by in corpus (11)

• Excitonic gap formation and condensation in the bilayer graphene structure
• Real-space cluster dynamical mean-field approach to the Falicov-Kimball model: An alloy-analogy approach
• An On-Site Density Matrix Description of the Extended Falicov--Kimball Model at Finite Temperatures
• DMRG study of exciton condensation in the extended Falicov-Kimball model
• Phase coherence and spectral functions in the two-dimensional excitonic systems
• Probing phase coherence via density of states for strongly correlated excitons
• Density of states and excitonic condensation in the double layer correlated systems
• Effects of correlated hopping on electronic ferroelectricity in the extended Falicov-Kimball model in two dimensions
• A Description of Phases with Induced Hybridisation at Finite Temperatures
• Excitonic gap formation in neutral bilayer structures
• Density of states in the bilayer graphene with the excitonic pairing interaction