Quantum Tunnelling Demonstration using a Low-cost Experimental Setup

A simple and reliable experimental setup that illustrates one-dimensional quantum tunnelling effect is introduced. The main elements in this setup are the fabrication of sharp tips, and the sensing and approaching mechanism. A technique to fabricate very sharp tips is described, with tips made of 60 μm thick tungsten wire easily obtainable from car light bulbs. The technique produced tips with aspect ratios of 2 and tip diameter of 15 nm ±4.5 nm. A mechanical configuration to scale down semi-lineal displacement is suggested along with an experimental setup, including circuitry and measurement.