Magnetic quantum crystals
In experiments with ultracold rubidium atoms LMU/MPQ scientists create magnetic quantum crystals made of gigantic Rydberg atoms.
Materials with a defined crystal structure are a familiar phenomenon in condensed matter physics. A crystal exhibits a regular structure, due to a periodic repetition of its building blocks. The resulting geometry depends on external parameters such as pressure and temperature, and even more strongly on the type of interaction between the building blocks, for example the Coulomb force or the van der Waals force. For the first time a team of scientists around Prof. Immanuel Bloch (Director at MPQ und Chair of Experimental Physics at the LMU), in cooperation with theorists from Dresden, have succeeded in generating incompressible magnetic quantum crystals containing several hundred rubidium atoms. Depending on the shape of the crystal and the strength of the magnetization different geometries are formed. In these experiments the scientists exploit the extremely enhanced interactions between highly excited gigantic Rydberg atoms that have a diameter a thousand times larger than ground state atoms.