Abstract
An even-denominator rational quantum number has been observed in the Hall resistance of a two-dimensional electron system. At partial filling of the second Landau level ν=2+(1/2= 5) / 2 and at temperatures below 100 mK, a fractional Hall plateau develops at =(h/)/(5/2 defined to better than 0.5%. Equivalent even-denominator quantization is absent in the lowest Landau level under comparable conditions.
- Received 24 July 1987
DOI:https://doi.org/10.1103/PhysRevLett.59.1776
©1987 American Physical Society