Excitation of robust materials

So-called topological materials have special electronic properties, which are very robust against external perturbations. In tungsten ditelluride such a topologically protected state can be ''broken up'' using special laser pulses within picoseconds and thus change its properties. This could be a key requirement for realising extremely fast, optoelectronic switches. For the first time, physicists observed changes to the electronic properties of this material in experiments in real-time.