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arXiv · 0810.2274

Observation of a Fractional Quantum Hall State at $ν=1/4$ in a Wide GaAs Quantum Well

D. R. Luhman·W. Pan·D. C. Tsui·L. N. Pfeiffer·K. W. Baldwin·K. W. West
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Abstract

We report the observation of an even-denominator fractional quantum Hall (FQH) state at $ν=1/4$ in a high quality, wide GaAs quantum well. The sample has a quantum well width of 50 nm and an electron density of $n_e=2.55\times10^{11}$ cm$^{-2}$. We have performed transport measurements at $T\sim35$ mK in magnetic fields up to 45 T. When the sample is perpendicular to the applied magnetic field, the diagonal resistance displays a kink at $ν=1/4$. Upon tilting the sample to an angle of $θ=20.3^o$ a clear FQH state at emerges at $ν=1/4$ with a plateau in the Hall resistance and a strong minimum in the diagonal resistance.

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D. R. Luhman, W. Pan, D. C. Tsui, L. N. Pfeiffer, K. W. Baldwin, K. W. West. 2008-10-13. Observation of a Fractional Quantum Hall State at $ν=1/4$ in a Wide GaAs Quantum Well. https://doi.org/10.1103/physrevlett.101.266804

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