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arXiv · 2208.05504

Spontaneous fractional Josephson current from parafermions

Kishore Iyer·Amulya Ratnakar·Aabir Mukhopadyaya·Sumathi Rao·Sourin Das
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Abstract

We study a parafermion Josephson junction (JJ) comprising a pair of counter-propagating edge modes of two quantum Hall (QH) systems, proximitized by an s-wave superconductor. We show that the difference between the lengths (which can be controlled by external gates) of the two counter-propagating chiral edges at the Josephson junction, can act as a source of spontaneous phase bias. For the Laughlin filling fractions, $\nu = 1/m,~ m \in 2\mathbb{Z}+1$, this leads to an electrical control of either Majorana $(m=1)$ or parafermion $(m\neq 1)$ zero modes.

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Kishore Iyer, Amulya Ratnakar, Aabir Mukhopadyaya, Sumathi Rao, Sourin Das. 2022-08-10. Spontaneous fractional Josephson current from parafermions. https://doi.org/10.1103/physrevb.107.l121408

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