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arXiv · 0903.4085

Tuning non-linear charge transport between integer and fractional quantum Hall states

Stefano Roddaro·Nicola Paradiso·Vittorio Pellegrini·Giorgio Biasiol·Lucia Sorba·Fabio Beltram
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Abstract

Controllable point junctions between different quantum Hall phases are a necessary building block for the development of mesoscopic circuits based on fractionally-charged quasiparticles. We demonstrate how particle-hole duality can be exploited to realize such point-contact junctions. We show an implementation for the case filling factors $\nu=1$ and $\nu^*\le1$ in which both the fractional filling $\nu^*$ and the coupling strength can be finely and independently tuned. A peculiar crossover from insulating to conducting behavior as $\nu^*$ goes from 1/3 to 1 is observed. These results highlight the key role played on inter-edge tunneling by local charge depletion at the point contact.

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Stefano Roddaro, Nicola Paradiso, Vittorio Pellegrini, Giorgio Biasiol, Lucia Sorba, Fabio Beltram. 2009-03-24. Tuning non-linear charge transport between integer and fractional quantum Hall states. https://doi.org/10.1103/physrevlett.103.016802

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