1.   For example, the aluminum dioxide insulating layer in the tiny sandwich of iron-cobalt magnets that makes up the experimental memory cell is only four atoms thick.

2.   Porous silicon has a layer of hydrogen just one atom thick covering its surface.

3.   The team found that the silicon dioxide layer needed to be four or five atoms thick to act as an insulator.

4.   To make nanotubes, carbon vapor is condensed into sheets of graphite one atom thick, which spontaneously adopt a form resembling chicken wire.