School of Physics Lecture Demonstration Manual

Na-9 Quantum Mechanical Tunnelling

Published: Friday 17 March 2006 - Updated: Thursday 31 March 2011


To demonstrate Quantum Mechanical tunnelling with microwaves.



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QM Tunnelling


A microwave transmitter is directed to one face of a wax prism. A second matching prism is located close to, but separated from the first prism by about a cm making a square with a small air gap. The receiver may be moved from the direct in line position to the perpendicular receiving position. As the air gap is less than a wavelength (3cm) quantum tunnelling on a macrosopic scale occurs giving an appreciable signal in the direct line of sight position.

Safety notes

Electrical safety 


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