https://www.sciencedaily.com/releases/2018/11/181102105953.htm

Similar to bits in conventional computers, QuBits are the smallest unit of information in quantum systems. Big companies like Google and IBM are competing with research institutes around the world to produce an increasing number of entangled QuBits. The clear motivation is to develop a functioning quantum computer. A research group at the University of Vienna and the Austrian Academy of Sciences, however, is pursuing a new path to increase the information capacity of complex quantum systems.

The idea behind it is simple: instead of just increasing the number of particles involved, the complexity of each system is increased. "The special thing about our experiment is that for the first time it entangles three photons beyond the conventional two-dimensional nature," explains Manuel Erhard, first author of the study. For this purpose, the Viennese physicists use quantum systems which have more than two possible states -- in this particular case, the angular momentum of individual light particles. These individual photons now have a higher information capacity than QuBits. However, the entanglement of these light particles turned out to be difficult on a conceptual level. The researchers overcame this challenge with a ground-breaking idea: a computer algorithm that autonomously searches for an experimental implementation.