NRG Study of an Inversion-Symmetric Interacting Model: Universal Aspects of its Quantum Conductance

Axel Freyn (1) , Jean-Louis Pichard (1)

1 SPEC - UMR3680 - Service de physique de l'état condensé

We consider scattering of spinless fermions by an inversion-symmetric interacting model characterized by three parameters (interaction U, internal hopping t_d and coupling t_c). Mapping this spinless model onto an Anderson model with Zeeman field, we use thenumerical renormalization group for studying the particle-hole symmetric case. We show that the zero temperature limit is characterized by a line of free-fermion fixed points and a scale \tau(U,t_c) of t_d for which there is perfect transmission. The quantum conductance and the low energy excitations of the model are given by universal functions of t_d/\tau if t_d < \Gamma and of t_d/t_c^2 if t_d > \Gamma, \Gamma = t_c^2 being the level width of the scatterer. This universal regime becomes non-perturbative when U exceeds \Gamma.

Mots clés: Conductance quantique; interaction electron-electron; algorithme NRG; effet Kondo orbital; systèmes mésoscopiques

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Axel Freyn, Jean-Louis Pichard. NRG Study of an Inversion-Symmetric Interacting Model: Universal Aspects of its Quantum Conductance. 2009. ⟨hal-00373518⟩