Modeling and simulation of an ultrasensitive electron tunneling position/force nanosensor

An ultrasensitive position/force nanosensor model was constructed and theoretically characterized. This model is based on a core-shell nanostructure with an inter-segment nanogap embedded, which forms an alignment-free metal-insulator-metal (MIM) junction. The occurrence of the tunneling effect enables the exponential scaling of the change of the displacement or force using tunneling current, which guarantees an ultrasensitive transduction. The simulation indicates that the combination of proper core materials and optimized design of the nanostructure could highly enhance the transduction performance. The simulation results provide instructions for the implementation of such ultrasensitive tunneling nanosensors, which in turn open new ground for tunneling-effect-based sub-nanoscale or even picoscale position/force detection.