Nature has realized a manifold of suprising nanostructures that we can also harvest to illustrate the workings of quantum mechanics.
Here we demonstrate in particular the possibility to delocalize dye molecules across the nanopores of the frustule (skeleton) of the silicified alga Amphipleura Pellucida. With only 180 nm separation between the alga pores this structure is very similar to those made by costly focused ion beam writing.
The remaining irregularities contribute to a sligth smearing of the interference pattern.
Since silicified alga can be collected at the sea shore (our specimen was collected in at a beach in the UK) the costs for nanofabrication can be eliminated for simple demonstration experiments.