With a simple twist of the fingers, one can create a beautiful spiral from a deck of cards. In the same way, Foundry users and scientists have created new inorganic crystals made of stacks of atomically thin sheets that unexpectedly spiral like a nanoscale card deck.
Their surprising structures, reported in a new study in the journal Nature, may yield unique optical, electronic and thermal properties, including superconductivity, the researchers say.
These helical crystals are made of stacked layers of germanium sulfide, a semiconductor material that, like graphene, readily forms sheets that are only a few atoms thick. Such “nanosheets” are usually referred to as “2D materials.”