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Fractional quantum Hall effect without energy gap

S. S. Murzin·S. I. Dorozhkin·G. E. Tsydynzhapov·V. N. Zverev
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Abstract

In the fractional quantum Hall effect regime we measure diagonal ($ρ_{xx}$) and Hall ($ρ_{xy}$) magnetoresistivity tensor components of two-dimensional electron system (2DES) in gated GaAs/Al$_{x}$Ga$_{1-x}$As heterojunctions, together with capacitance between 2DES and the gate. We observe 1/3- and 2/3-fractional quantum Hall effect at rather low magnetic fields where corresponding fractional minima in the thermodynamical density of states have already disappeared manifesting complete suppression of the quasiparticle energy gaps.

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S. S. Murzin, S. I. Dorozhkin, G. E. Tsydynzhapov, V. N. Zverev. 2006-03-31. Fractional quantum Hall effect without energy gap. https://doi.org/10.1134/s0021364007140159

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