Fractionalization in spontaneous integer quantum Hall systems

Rodrigo A. Muniz; Armin Rahmani; Ivar Martin

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arXiv · 1112.3347

Fractionalization in spontaneous integer quantum Hall systems

Rodrigo A. Muniz·Armin Rahmani·Ivar Martin

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Abstract

It is widely believed that integer quantum Hall systems do not have fractional excitations. Here we show the converse to be true for a class of systems where integer quantum Hall effect emerges spontaneously due to the interplay of itinerant electrons and noncoplanar magnetic ordering. We show that magnetic $Z_2$ vortices in such systems, whose topological stability is guaranteed by the structure of the order parameter, indeed carry fractional charge.

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Rodrigo A. Muniz, Armin Rahmani, Ivar Martin. 2012-08-01. Fractionalization in spontaneous integer quantum Hall systems. https://arxiv.org/abs/1112.3347

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