PhotonQ project

The idea behind quantum computers is that they are expected to one day solve problems that are unaccessible to classic computer systems. However, before such computers can be used in practice, they will have to process considerably more qubits and exhibit lower error rates. A joint research group around Professor Stefanie Barz of the University of Stuttgart is currently developing a photonic quantum processor, which will allow the realization of quantum algorithms with a small number of qubits and, in the long run, enable rapid scaling to qubit numbers relevant to practical applications.

Last year, integrated optical components made of aluminum nitride (AlN) and thermal phase shifters with heating elements made of titanium nitride (TiN) were developed for PhotonQ. AlN waveguides enable low-loss and fast phase modulation through piezo-induced material strain (see picture on front page). TiN heaters, on the other hand, allow very low-loss phase modulation in silicon waveguides due to their short design.