  Bilayer quantum Hall states support a flow of nearly dissipationless
staggered current which can only decay through collective channels. We study
the dominant finite-temperature dissipation mechanism which in narrow bars is
driven by thermal nucleation of pseudospin solitons. We find the
finite-temperature resistivity, predict the resulting staggered current-voltage
characteristics, and calculate the associated zero-temperature critical
staggered current and gate voltage.
