Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer).
Quantum dots are crystals of a fluorescent semiconductor material with a diameter of as few as 10 to 100 atoms (2-10 nm). They are used as labels for imaging molecules because of their very narrow fluorescence spectra, brightness and resistance to photobleaching.
Resonant driving of a nanoscale quantum system coupled to a microscopic mechanical resonator may have uses in precision sensing and quantum information. The authors realize this by tailoring the geometry of a semiconductor nanowire embedding a quantum dot, detecting sub-picometre displacements.
The efficiency and indistinguishability of single-photon emission by a quantum dot optically coupled to a microcavity and to a waveguide are theoretically investigated. Owing to unavoidable phonon sideband, they can never reach 100% simultaneously.
Multiple exciton generation, in which two electron–hole pairs are generated from the absorption of one high-energy photon, has been demonstrated to improve efficiency in quantum-dot-based solar cells. Now, a photoelectrochemical system using PbS quantum dots is shown to drive hydrogen evolution with external quantum efficiency over 100%.