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Fractional charge excitations in fermionic ladders

B. N. Narozhny·S. T. Carr·A. A. Nersesyan
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Abstract

The system of interacting spinless fermions hopping on a two-leg ladder in the presence of an external magnetic field is shown to possess a long range order: the bond density wave or the staggered flux phase. In both cases the elementary excitations are $Z_2$ kinks and carry one half the charge of an electron.

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B. N. Narozhny, S. T. Carr, A. A. Nersesyan. 2004-07-22. Fractional charge excitations in fermionic ladders. https://doi.org/10.1103/physrevb.71.161101

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