Deviatov, E. V. and Dolgopolov, V. T. and Würtz, A. and Wixforth, A. and Wegscheider, Werner and Campman, K. L. and Gossard, A. C.
Topological defects in the edge-state structure in a bilayer electron system.
Physical Review B (PRB) 72 (4), 041305R.
We experimentally demonstrate formation of pointlike topological defects in the edge-state structure in the quantum Hall effect regime. By using of a selective population technique, we investigate equilibration processes between the edge states in bilayer electron structures with a high tunneling rate between layers. Unexpected flattening of the I-V curves in a perpendicular magnetic field at a specific filling factor combination and the recovery of the conventional nonlinear I-V characteristics in tilted fields give a strong evidence for the existence of topological defects.