1. Nano-Science Center and Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
2. Department of Physics, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
3. Nano-Science Center and Department of Chemistry, Copenhagen University, DK-2100 Copenhagen, Denmark
4. NNF Quantum Computing Programme, Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark