  It was recently predicted [J. Phys.: Condens. Matter 18, 11059 (2006)] that
turbulence of the electron flow may develop at nonadiabatic nanoscale junctions
under appropriate conditions. Here we show that such an effect leads to an
asymmetric current-induced magnetic field on the two sides of an otherwise
symmetric junction. We propose that by measuring the fluxes ensuing from these
fields across two surfaces placed at the two sides of the junction would
provide direct and noninvasive evidence of the transition from laminar to
turbulent electron flow. The flux asymmetry is predicted to first increase,
reach a maximum and then decrease with increasing current, i.e. with increasing
amount of turbulence.
