Research Highlights | Published:


Transistor uses single photons

Nature volume 511, page 511 (31 July 2014) | Download Citation

Two teams in Germany have built transistors that control light at the single-photon level.

Transistors that switch light instead of electrical current can enable ultra-fast computing. But making optical transistors with 'gain' — when one photon affects many others to drive further switches — has been tricky because photons do not interact with each other.

To overcome this problem, a team at the Max Planck Institute of Quantum Optics in Garching and a separate group at the University of Stuttgart passed a single photon through a cloud of ultracold rubidium atoms. The photon converted one atom into a type of large, excited particle called a Rydberg atom, which blocked the next photon from passing through.

In the Stuttgart team's transistor, one photon diverted another 10, whereas in the Max Planck device, a photon controlled a further 20.

About this article

Publication history





    By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

    Newsletter Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing