Noise due to neutral modes in the v=2/3 fractional quantum Hall state

Abstract

We theoretically study charge noise generated by excited neutral modes, which impinge on the quantum point contact of a quantum Hall bar with filling fraction v=2/3. The noise is computed for thermally excited neutral modes as well as for biased neutral modes with dipole-fermion excitations. Within the dipole-fermion picture, we show that the noise arising from two colliding modes can be suppressed due to Pauli-blocking and be non-universal due to random edge disorder, but becomes universal upon disorder-averaging. The ratio of noise due to two colliding neutral modes and noise due to only one such mode is smaller for dipole-fermions than for thermal excitations, thus providing evidence for the different quantum statistics of the two types of excitations.