Exploring the Limits of Small: Molecular Electronics
Smaller is better, we’ve been told, but in the age of Intel’s 32 nm transistor it is increasingly challenging to scale down electronic circuitry because quantum mechanics begins to play a role. The use of individual molecules as circuit elements (hence the name molecular electronics) provides an opportunity for scientists to harness quantum mechanics and use it to control conduction at the nanoscale. Both the chemical structure of the molecule used and its geometry within the junction can dramatically affect the conduction properties of a molecular device, which means that molecules can act not only as wires but also as diodes, switches, and even single-electron transistors. Molecules offer unique properties not available to silicon nanostructures, which allows for totally new switching mechanisms in circuits (e.g. light mediated). Molecular devices will be discussed in the context of quantum mechanical charge transport mechanisms, including tunneling and thermally activated hopping, and the talk will conclude with a discussion of exciting new molecular devices.