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arXiv · 2103.06826

Non-topological fractional fermion number in the Jackiw-Rossi model

Caio Almeida·Alberto Alonso-Izquierdo·Rodrigo Fresneda·Juan Mateos Guilarte·Dmitri Vassilevich
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Abstract

We compute the vacuum fermion current in $(2+1)$ dimensional Jackiw-Rossi model by using the $1/m$ expansion. The current is expressed through a weighted $\eta$-function with a matrix weight. In the presence of such a weight, the usual proof of topological nature of $\eta(0)$ is not longer applicable. Direct computations confirm the following surprising result: the fermion number induced by vortices in the Jackiw-Rossi model is \textit{not} topological.

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Caio Almeida, Alberto Alonso-Izquierdo, Rodrigo Fresneda, Juan Mateos Guilarte, Dmitri Vassilevich. 2021-03-11. Non-topological fractional fermion number in the Jackiw-Rossi model. https://doi.org/10.1103/physrevd.103.125015

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