Barrier induced transfer inefficiency and current limiting in acoustic charge transport devices

The ACT (acoustic charge transfer) current capacity for a fixed transfer inefficiency is fount to decrease linearly with applied barrier field in good agreement with an empirical model based on one-dimensional theory. In the absence of barrier fields, a residual current capacity loss is observed which ranges from 10-14% of the extrapolated unperturbed current capacity and increases with decreasing SAW (surface acoustic wave) potential. The frequency-response roll-of for a fixed current level is undetectable below a threshold barrier field and increases exponentially with barrier field above the threshold. In addition, the diffusion barrier height reduction between adjacent SAW potential wells is experimentally found to be linear with respect to applied barrier field and independent of current level. Finally, a means to estimate the impact of grating structures and gaps between Schottky plates on current capacity is given