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arXiv · 1904.01589

Variational Ansatz for an Abelian to non-Abelian Topological Phase Transition in $\nu = 1/2 + 1/2$ Bilayers

Valentin Crépel·Benoit Estienne·Nicolas Regnault
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Abstract

We propose a one-parameter variational ansatz to describe the tunneling-driven Abelian to non-Abelian transition in bosonic $\nu=1/2+1/2$ fractional quantum Hall bilayers. This ansatz, based on exact matrix product states, captures the low-energy physics all along the transition and allows to probe its characteristic features. The transition is continuous, characterized by the decoupling of antisymmetric degrees of freedom. We futhermore determine the tunneling strength above which non-Abelian statistics should be observed experimentally. Finally, we propose to engineer the inter-layer tunneling to create an interface trapping a neutral chiral Majorana. We microscopically characterize such an interface using a slightly modified model wavefunction.

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Valentin Crépel, Benoit Estienne, Nicolas Regnault. 2019-04-02. Variational Ansatz for an Abelian to non-Abelian Topological Phase Transition in $\nu = 1/2 + 1/2$ Bilayers. https://doi.org/10.1103/physrevlett.123.126804

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