In situ alignment of carbon nanocoils and their field emission behavior induced by an electric field

The alignment of nanocoils by an electric field was observed in situ inside a focused ion beam microscope. This alignment occurred at relatively low fields, before the onset of electron field emission. The emission behavior of individual nanocoils was also studied using a field emission probe system. The robust coils reached high emission currents, with more than 10 μA coming from individual coils at fields stronger than 4 V/μm. The emission behavior, however, was not wholly consistent with conventional field emission theory. Analysis of the data showed non-linear Fowler-Nordheim behavior. This phenomenon is usually attributed to thermal effects, but numerical calculations show that cannot be the case. The data plotted linearly on a Schottky plot, which should not be possible due to Schottky temperature dependence and resistive heating during emission.