arXiv:1201.5323 · Physical Review B
Numerical method for nonlinear steady-state transport in one-dimensional correlated conductors
Malcolm Einhellinger, Alex Cojuhovschi, Eric Jeckelmann
Abstract
We present a method for investigating the steady-state transport properties of one-dimensional correlated quantum systems. Using a procedure based on our analysis of finite-size effects in a related classical model ($LC$ line) we show that stationary currents can be obtained from transient currents in finite systems driven out of equilibrium. The nonequilibrium dynamics of correlated quantum systems is calculated using the time-evolving block decimation method. To demonstrate our method we determine the full $I$-$V$ characteristic of the spinless fermion model with nearest-neighbor hopping ${t}_{\text{H}}$ and interaction ${V}_{\text{H}}$ using two different setups to generate currents (turning on/off a potential bias). Our numerical results agree with exact results for noninteracting fermions (${V}_{\text{H}}=0$). For interacting fermions we find that in the linear regime $eV\ensuremath{\ll}4{t}_{\text{H}}$ the current $I$ is independent from the setup and our numerical data agree with the predictions of the Luttinger liquid theory combined with the Bethe Ansatz solution. For larger potentials $V$ the steady-state current depends on the current-generating setup and as $V$ increases we find a negative differential conductance with one setup while the currents saturate at finite values in the other one. Both effects are due to finite renormalized bandwidths.