A single molecule can act as a nanometre-sized microphone.
Michel Orrit and his colleagues at the University of Leiden in the Netherlands placed molecules of dibenzoterrylene within a crystal a few degrees above absolute zero and attached a tuning fork to the crystal. Hitting the fork caused vibrations that stretched and compressed the crystal, which in turn shifted the frequency at which the molecules emitted light. The light-frequency readout allowed the team to detect the vibrations from an individual molecule.
The nano-microphone could be used as an ultra-sensitive detector for very slight vibrations, such as from tiny oscillators that measure the properties of quantum systems, the authors say.