Abstract
We report ultralow temperature experiments on the obscure fractional quantum Hall effect at Landau level filling factor υ=5/2 in a very high-mobility specimen of μ=1.7×107cm2/Vs. We achieve an electron temperature as low as ˜4mK, where we observe vanishing Rxx and, for the first time, a quantized Hall resistance, Rxy=h/(5/2)e2 to within 2 ppm. Rxy at the neighboring odd-denominator states υ=7/3 and 8/3 is also quantized. The temperature dependences of the Rxx minima at these fractional fillings yield activation energy gaps Δ5/2=0.11, Δ7/3=0.10, and Δ8/3=0.55K.
Original language | English (US) |
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Pages (from-to) | 3530-3533 |
Number of pages | 4 |
Journal | Physical review letters |
Volume | 83 |
Issue number | 17 |
DOIs | |
State | Published - Jan 1 1999 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy