Fractional Quantum Hall Effect at Landau Level Filling nu=4/11
  We report low temperature electronic transport results on the fractional quantum Hall effect of composite fermions at Landau level filling nu = 4/11 in a very high mobility and low density sample. Measurements were carried out at temperatures down to 15mK, where an activated magnetoresistance Rxx and a quantized Hall resistance Rxy, within 1% of the expected value of h/(4/11)e^2, were observed. The temperature dependence of the Rxx minimum at 4/11 yields an activation energy gap of ~ 7 mK. Developing Hall plateaus were also observed at the neighboring states at nu = 3/8 and 5/13. 
W. Pan, K.W. Baldwin, K.W. West, L.N. Pfeiffer, and D.C. Tsui
cond-mat.mes-hall