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arXiv · cond-mat/9907356

Exact Quantization of Even-Denominator Fractional Quantum Hall State at $ν$=5/2 Landau Level Filling Factor

W. Pan·J. -S. Xia·V. Shvarts·E. D. Adams·H. L. Stormer·D. C. Tsui·L. N. Pfeiffer·K. W. Baldwin·K. W. West
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Abstract

We report ultra-low temperature experiments on the obscure fractional quantum Hall effect (FQHE) at Landau level filling factor $ν$=5/2 in a very high mobility specimen of $μ=1.7 \times 10^7$ cm$^2$/Vs. We achieve an electron temperature as low as $\sim$ 4~mK, where we observe vanishing $R_{xx}$ and, for the first time, a quantized Hall resistance, $R_{xy}=h/(5/2e^2)$ to within 2 ppm. $R_{xy}$ at the neighboring odd-denominator states $ν$=7/3 and 8/3 is also quantized. The temperature dependences of the $R_{xx}$-minima at these fractional fillings yield activation energy gaps $Δ_{5/2}$=0.11K, $Δ_{7/3}$=0.10K, and $Δ_{8/3}$=0.055K.

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W. Pan, J. -S. Xia, V. Shvarts, E. D. Adams, H. L. Stormer, D. C. Tsui, L. N. Pfeiffer, K. W. Baldwin, K. W. West. 1999-07-23. Exact Quantization of Even-Denominator Fractional Quantum Hall State at $ν$=5/2 Landau Level Filling Factor. https://doi.org/10.1103/physrevlett.83.3530

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