Quantum criticality and first-order transitions in the extended periodic Anderson model

Abstract

We investigate the behavior of the periodic Anderson model in the presence of $d$-$f$ Coulomb interaction ($U_{df}$) using mean-field theory, variational calculation, and exact diagonalization of finite chains. The variational approach based on the Gutzwiller trial wave function gives a critical value of $U_{df}$ and two quantum critical points (QCPs), where the valence susceptibility diverges. We derive the critical exponent for the valence susceptibility and investigate how the position of the QCP depends on the other parameters of the Hamiltonian. For larger values of $U_{df}$, the Kondo regime is bounded by two first-order transitions. These first-order transitions merge into a triple point at a certain value of $U_{df}$. For even larger $U_{df}$ valence skipping occurs. Although the other methods do not give a critical point, they support this scenario.

8 pages, 7 figures

References in corpus (5)

• Signatures of valence fluctuations in CeCu2Si2 under high pressure
• Superconductivity emerging near quantum critical point of valence transition
• Valence Instability and Superconductivity in Heavy Fermion Systems
• Quantum phase transitions in the extended periodic Anderson model
• Pressure-induced change of the pairing symmetry in superconducting CeCu2Si2

Cited by in corpus (4)

• Valence Fluctuations in the Extended Anderson Lattice Model with Quasiperiodicity
• Interorbital interaction in the one-dimensional periodic Anderson model: A density-matrix renormalization-group study
• Competition between Hund's coupling and Kondo effect in a one-dimensional extended periodic Anderson model
• Magnetic phases of the periodic Anderson model in two dimensions