The development of computers until now has been achieved by packing continually more transistors into chips—that is, by making transistors ever smaller. However, in recent years it has been questioned whether such transistors can actually function as transistors if shrunk until their constituent atoms and molecules number only several thousand. It is thought that when the length of a gate, a component of a transistor, is reduced to several tens of nanometers, the strong manifestation of quantum properties will render the transistor no longer functional as a computation element.

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A proposal made in response to this is the single-electron transistor (SET). This transistor makes use of tunneling and other phenomena peculiar to the quantum world in order to control individual electrons one by one and to perform computation. It is thought that quantum dots will play a particularly key role in achieving SETs. In theory, this achievement will enable far higher performance and lower power consumption in computers.