Fermi surface renormalization and confinement in two coupled metallic chains

Abstract

Using a non-perturbative functional renormalization group approach involving both fermionic and bosonic fields we calculate the interaction-induced change of the Fermi surface of spinless fermions moving on two chains connected by weak interchain hopping t_{bot}. We show that interchain backscattering can strongly reduce the distance Delta between the Fermi momenta associated with the bonding and the antibonding band, corresponding to a large reduction of the effective interchain hopping t_{bot}^{*} A self-consistent one-loop approximation neglecting marginal vertex corrections and wave-function renormalizations predicts a confinement transition for sufficiently large interchain backscattering, where the renormalized t_{bot}^{*} vanishes. However, a more accurate calculation taking vertex corrections and wave-function renormalizations into account predicts only weak confinement in the sense that 0< | t_{bot}^{*} | << | t_{bot} |. Our method can be applied to other strong-coupling problems where the dominant scattering channel is known.

15 RevTex pages, 11 figures; final version as published in Phys. Rev. B; changes: figure with weak coupling RG flow added; more extensive discussion of previous work added; some references added

References in corpus (3)

• Collective fields in the functional renormalization group for fermions, Ward identities, and the exact solution of the Tomonaga-Luttinger model
• Interaction-induced Fermi surface deformations in quasi one-dimensional electronic systems
• Two-loop renormalization-group theory for the quasi-one-dimensional Hubbard model at half filling

Cited by in corpus (2)

• Functional renormalization group approach to the Anderson impurity model
• Confined coherence in quasi-one-dimensional metals