Our electronic quantum IDs use the fact that electrons can only have very specific energies when their motion is restricted at the atom scale. The exact value of these allowed energies are sensitive to atomic scale imperfections. Our device generates IDs using a small semiconductor diode designed around this principle.
In an ordinary conducting wire, energies of electrons can take any value as they are free to travel around. When their motion is restricted, by energy barriers such as crystal lattices, electrons take up specific energies. This is called quantum confinement, a direct consequence of the Schrödinger Equation. The quantum confinement changes slightly each time a diode is made, which means every device produces a unique signature.
If you would like to know more about how this device works there is a BBC News article about it here, a more technical document here, a scientific paper published in Nature’s Scientific Reports and a granted patent.
In the next element of the exhibition we look at an optical security tag that is based upon a similar principle.