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arXiv · 2108.03259

Tunneling maps of interacting electrons in real time: anomalous tunneling in quantum point-contacts beyond the steady state regime

Abstract

Strongly correlated transport of interacting electrons through the one-dimensional tunnel contact is considered within the Luttinger liquid model of one-dimensional electrodes on arbitrary time scales $ t> \hbar /\Lambda_{g} $. Using previous results, namely, the Self-equilibration theorem proven in Ref.[G.Skorobagatko, Ann.Phys., 422, 168298 (2020)] the exact distribution functions $ P(N,t) $ for the probabilities of $ N $ electrons to tunnel through the contact during the fixed time interval $ t $ are derived and plotted as 3D intensity graphs called real-time tunneling maps in a whole available region of Luttinger liquid correlation parameter values, bias voltages, and temperatures. The tunneling maps being obtained reveal tunneling anomalies -unusually high tunneling probabilities for the small numbers of electrons on the short-time scales beyond the steady state regime of electron tunnel transport. Especially, this concerns the case of strong short-range electron-electron interaction in the leads at $ g \lesssim 1/2 $. The effect being found can be treated as the direct consequence of the self-equilibration phenomenon. It is shown that features of such an anomalous electron tunneling beoynd the steady state regime can be used for precise experimental measurements of small differences between Luttinger liquid correlation parameter values in different one-dimensional quantum-point contacts.

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Taras Hutak, Gleb Skorobagatko. 2021-08-06. Tunneling maps of interacting electrons in real time: anomalous tunneling in quantum point-contacts beyond the steady state regime. https://doi.org/10.1016/j.physleta.2022.128246

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