Cold and trapped metastable noble gases

Cold atomic gases have numerous applications, ranging from matter-wave interferometry to many-body physics. Atoms from the noble gas family play a special role in this research. Indeed each atom must be prepared in a metastable electronic state in order to be manipulated by laser light, and it thus carries a large internal energy. This article surveys the specific properties of these metastable noble gases, such as their unique collision dynamics. The relevance of these gases for metrology is also discussed.