Periodic negative differential conductance in a single metallic   nano-cage
  We report a bi-polar multiple periodic negative differential conductance (NDC) effect on a single cage-shaped Ru nanoparticle measured using scanning tunneling spectroscopy. This phenomenon is assigned to the unique multiply-connected cage architecture providing two (or more) defined routes for charge flow through the cage. This, in turn, promotes a self- gating effect, where electron charging of one route affects charge transport along a neighboring channel, yielding a series of periodic NDC peaks. This picture is established and analyzed here by a theoretical model. 
Yehonadav Bekenstein and Kathy Vinokurov and Tal J. Levy and Eran   Rabani and Uri Banin and Oded Millo
cond-mat.mes-hall cond-mat.str-el