Spectral functions of two-band spinless fermion and single-band spin-1/2 fermion models

Abstract : We examine zero-temperature one-particle spectral functions for the one-dimensional two-band spinless fermions with different velocities and general forward-scattering interactions. By using the bosonization technique and diagonalizing the model to two Tomonaga-Luttinger liquid Hamiltonians, we obtain general expressions for the spectral functions, which are given in terms of the Appell hypergeometric functions. For the case of identical two-band fermions, corresponding to the SU(2) symmetric spin-1/2 fermions with repulsive interactions, the spectral functions can be expressed in terms of the Gauss hypergeometric function and are shown to recover the double-peak structure suggesting the well-known "spin-charge" separation. By tuning the difference in velocities for the two-band fermions, we clarify the crossover in spectral functions from the spin-charge separation to the decoupled fermions. We discuss the relevance of our results to the spin-1/2 Hubbard model under a magnetic field, which can be mapped onto two-band spinless fermions.
Complete list of metadatas

https://hal-ens-lyon.archives-ouvertes.fr/ensl-00635751
Contributor : Edmond Orignac <>
Submitted on : Tuesday, October 25, 2011 - 6:14:23 PM
Last modification on : Thursday, April 19, 2018 - 2:54:03 PM

Links full text

Identifiers

Collections

Citation

Edmond Orignac, Masahisa Tsuchiizu, Yoshikazu Suzumura. Spectral functions of two-band spinless fermion and single-band spin-1/2 fermion models. Physical Review B : Condensed matter and materials physics, American Physical Society, 2011, 84 (16), pp.165128. ⟨10.1103/PhysRevB.84.165128⟩. ⟨ensl-00635751⟩

Share

Metrics

Record views

67