The nature of the fractional quantum Hall state with filling factor ν=2/3
and its edge modes continues to remain an open problem in low-dimensional
condensed matter physics. Here, we suggest an experimental setting to probe the
ν=2/3 edge by tunnel-coupling it to a ν=1 integer quantum Hall edge in
another layer of a two-dimensional electron gas (2DEG). In this double-layer
geometry, the momentum of tunneling electrons may be boosted by an auxiliary
magnetic field parallel to the two planes of 2DEGs. We evaluate the current as
a function of bias voltage and the boosting magnetic field. Its threshold
behavior yields information about the spectral function of the ν=2/3 edge,
in particular about the nature of the chiral edge modes. Our theory accounts
also for the effects of Coulomb interaction and disorder.Comment: 5 pages, 5 figures, and supplementary material (5 pages, 1 figure