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Effect of nonadiabatic switching of dynamic perturbations in 1d Fermi systems

Carlos M. Naón·Mariano J. Salvay·Marta L. Trobo
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Abstract

We study a two-dimensional fermionic QFT used to model 1D strongly correlated electrons in the presence of a time-dependent impurity that drives the system out of equilibrium. In contrast to previous investigations, we consider a dynamic barrier switched on at a finite time. We compute the total energy density (TED) of the system and establish two well defined regimes in terms of the relationship between the frequency of the time-dependent perturbation $Ω$ and the electron energy $ω$. Finally, we derive a relaxation time $t_{R}$ such that for times shorter than $t_{R}$ the finite-time switching process is relevant.

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Carlos M. Naón, Mariano J. Salvay, Marta L. Trobo. 2004-09-23. Effect of nonadiabatic switching of dynamic perturbations in 1d Fermi systems. https://doi.org/10.1103/physrevb.70.195109

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