| One of the key features of the quantum Hall effect (QHE) is the fractional charge and statistics of quasiparticles. Fractionally charged anyons accumulate non-trivial phases when they encircle each other. In the case of non-Abelian statistics predicted in some QHE systems, even the direction of the quantum-state vector in the Hilbert space can change after a quasiparticle makes a full circle. Fractional charge was detected in the middle 90th. Probing exchange statistics is more difficult and has not been accomplished for identical anyons so far. We propose a method of detecting Abelian and non-Abelian fractional statistics based on the topologically non-trivial setup of the electronic Mach-Zehnder interferometer. This method does not suffer from the limitations of other approaches since the electric current through the interferometer is robust with respect to slow fluctuations of the trapped topological charge. The statistics can be determined from the dependence of the electric current through the interferometer on the magnetic field. For non-Abelian anyons the I-V curve is asymmetric. |
|