The negative resistance circuit was simulated and implemented to induce jumps from low energy to high energy orbits in nonlinear energy harvesters for their efficiency enhancement.

C. Lan, L. Tang*, W. Qin, 2017, “Obtaining High-Energy Responses of Nonlinear Piezoelectric Energy Harvester by Voltage Impulse Perturbations” (Accepted for publication by The European Physical Journal Applied Physics)