Chalmers team developed a time-dependent measurement probe

In voltage- and temperature-biased coherent conductors quantum screening effects occur if the conductor’s transmission is energy-dependent. In this article, we show that an additional ac-driven terminal can act as a probe for a direct readout of such effects, hitherto unexplored. 

We find that screening of charges induced by the static biases impacts already their standard linear thermoelectric response coefficients due to non-linear effects when accounting for the frequency of the time-dependent driving. Those effects should be observable under realistic experimental conditions and can literally be switched on and off with the ac-driving.

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