I investigate the nonlinear AC transport trough a quantum wire with an impurity in the presence of finite range electron-electron interactions. I discuss the influence of the spatial shape of the ac electric field onto transport properties of the system and find that the scaling behavior of the occupation probability of the sidebands depends on the range of the voltage drop. I observe a cross-over between the Tien-Gordon like scaling of the sidebands and a regime in which the scaling reflects the ranges of both, the electron-electron interaction and the electric field. Moreover, for intermediate interaction strengths, the non-linear differential conductance shows cusp-like periodic minima due to finite non-zero range of the interaction but are independent of the shape of the driving electric field.

references:

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