Concerning the possible states of a one-dimensional Fermi system

Salvador Miracle-Solé, Derek W. Robinson

Behnam Farid

We consider a specific generalization to spatial dimensions d greater than one of a formalism, based upon conservation laws and the associated ward identities, that exactly solves the one-dimensional Luttinger model, and expose its inadequacies for d > 1. We conclude that findings arrived at through application of this generalized formalism concerning systems of fermions with strong forward scattering, in particular that d = 1 would be the cross-over dimension from Luttinger- to Fermi-liquid state, are open to question.

Behnam Farid

We consider a specific generalization to spatial dimensions d greater than one of a formalism, based upon conservation laws and the associated ward identities, that exactly solves the one-dimensional Luttinger model, and expose its inadequacies for d > 1. We conclude that findings arrived at through application of this generalized formalism concerning systems of fermions with strong forward scattering, in particular that d = 1 would be the cross-over dimension from Luttinger- to Fermi-liquid state, are open to question.

R. F. Bishop

Vieri Mastropietro

Dante Marvin Kennes, C. Klöckner, V. Meden

We show that the single-particle spectral properties of gapless one-dimensional Fermi systems in the Luttinger liquid state reached at intermediate times after an abrupt quench of the two-particle interaction are highly indicative of the unusual nonequilibrium nature of this state. The line shapes of the momentum-integrated and -resolved spectral functions strongly differ from their ground state as well as finite temperature equilibrium counterparts. Using an energy resolution improved version of radio-frequency spectroscopy of quasi-one-dimensional cold Fermi gases, it should be possible to experimentally identify this nonequilibrium state by its pronounced spectral signatures.