Cooling with light

ETH researchers have cooled a nanoparticle to a record low temperature, thanks to a sophisticated experimental set-up that uses scattered laser light for cooling. Until now, no one has ever cooled a nanoparticle to such low temperatures in a photon cage. Dominik Windey and René Reimann – a doctoral student and postdoc in the group led by Lukas Novotny, Professor of Photonics – have succeeded in cooling a 140 nanometre glass bead down to a few thousandths of a degree above absolute zero.