Confinement of fractional quantum Hall states in narrow conducting channels

Confinement of small gapped fractional quantum Hall states facilitates quasiparticle manipulation and is an important step toward quasiparticle interference measurements. Demonstrated here is conduction through top gate defined, narrow channels in high density, ultrahigh mobility heterostructures. Transport evidence for the persistence of a correlated state at a filling fraction of 5/3 is shown in channels of 2 mu m length but is gated to near 0.3 mu m in width. The methods employed to achieve this confinement hold promise for interference devices proposed for studying potential non-Abelian statistics at a filling fraction of 5/2. (c) 2007 American Institute of Physics.