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Fractional Conductance in Strongly Interacting 1D Systems

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 Added by Gal Shavit
 Publication date 2019
  fields Physics
and research's language is English




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We study one dimensional clean systems with few channels and strong electron-electron interactions. We find that in several circumstances, even when time reversal symmetry holds, they may lead to two terminal fractional quantized conductance and fractional shot noise. The condition on the commensurability of the Fermi momenta of the different channels and the strength of interactions resulting in such remarkable phenomena are explored using abelian bosonization. Finite temperature and length effects are accounted for by a generalization of the Luther-Emery re-fermionization at specific values of the interaction strength. We discuss the connection of our model to recent experiments in confined 2DEG, featuring possible fractional conductance plateaus. One of the most dominant observed fractions, with two terminal conductance equals to $frac{2}{5}frac{e^{2}}{h}$, is found in several scenarios of our model. Finally, we discuss how at very small energy scales the conductance returns to an integer value and the role of disorder.



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