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We investigate the behavior of the dc voltage drop in a periodically driven double barrier structure (DBS) sensed by voltages probes that are weakly coupled to the system. We find that the four terminal resistance $R_{4t}$ measured with the probes lo cated outside the DBS results identical to the resistance measured in the same structure under a stationary bias voltage difference between left and right reservoirs. This result, valid beyond the adiabatic pumping regime, can be taken as an indication of the universal character of $R_{4t}$ as a measure of the resistive properties of a sample, irrespectively of the mechanism used to induce the transport.
We investigate the dc response of a 1D disordered ring coupled to a reservoir and driven by a magnetic flux with a linear dependence on time. We identify two regimes: (i) A localized or large length L regime, characterized by a dc conductance, g_{dc} , whose probability distribution P(g_{dc}) is identical to the one exhibited by a 1D wire of the same length L and disorder strength placed in a Landauer setup. (ii) A multifloquet regime for small L and weak coupling to the reservoir, which exhibits large currents and conductances that can be g_{dc} > 1, in spite of the fact that the ring contains a single electronic transmission channel. The crossover length between the multifloquet to the single channel transport regime, L_c, is controlled by the coupling to the reservoir.
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