     Excitonium discovered in real material
Excitons are pairs of electrons and holes inside a solid material that together behave like a single particle. It has long been suspected that when many such excitons exist in the same piece of matter, they can form a new state of matter, called excitonium. This new phase is essentially a single giant quantum state of excitons, called a BoseEinstein condensate. If that state does exist, it is expected to hold important clues to the understanding of many other mysterious phases of matter, including even hightermperature superconductivity. However, observing an exciton condensate in any real material has remained a much soughtafter goal of condensed matter physicists for decades. In a recent experiment, we now finally prove that this elusive state of matter really does exist.    For the full story, look here.     Finding all possible topological insulators in crystals
Topology has over the past decade or so developed into a central organising principle in the characterisation of phases of matter. While all topological phases of fermions in free space have been fully worked out, taking into account what happens in reallife materials that have additional crystal symmetries remains an active field of research. We recently took a step forwards in this area, by developing a complete classification of all possible crystalline topological insulators, in any dimension, in the presence of only lattice symmetries.  For the full story, look here.   Spirals of electron density
Spirals are an intriguing shape to find in the natural world because of their inherent handedness – turning either to the left or right as you move along them. The recent discovery that electrons within a solid material can spontaneously form into a corkscrew shape was an unexpected example of a spiral emerging in physics. The surprisingly straightforward explanation for this phenomenon has recently attracted some attention in the popular science media.    For the full story, look here.  


 "Stability and Absence of a Tower of States in Ferrimagnets"
Louk Rademaker, Aron Beekman, and Jasper van Wezel arXiv, 1909.11381 (2019) arXiv:1909.11381
 "An Introduction to Spontaneous Symmetry Breaking"
Aron J. Beekman, Louk Rademaker, and Jasper van Wezel arXiv, 1908.01820 (2019) arXiv:1909.01820
 "Topology in timereversal symmetric crystals"
Jorrit Kruthoff, Jan de Boer, Jasper van Wezel Phys. Rev. B, 100, 075116 (2019) doi:10.1103/PhysRevB.100.075116

Look here for the full list of publications.
