Phys. Rev. Lett. 107, 196802 (2011)

When a beam of light hits a thin metal film, some of it is absorbed and the rest is reflected. However, pierce the same film with a regular array of holes and, even if the hole size is smaller than the wavelength of the light, more light is transmitted than would be expected. Researchers have now shown that an effect similar to this so-called extraordinary optical transmission might also be seen with electrons.

In the analogy put forward by L. S. Petrosyan and colleagues, the optical apertures are replaced by quantum dots — nanostructures that can support discrete and localized electron states by virtue of their small size. The researchers considered a device in which this quantum-dot array is sandwiched between two electrical leads and calculated that the device's conductance per quantum dot in the array is significantly enhanced over the single-quantum-dot case. They attribute this to the fact that some of the quantum-dot electron states become delocalized because of coherent coupling to the leads.