“Peapods” such as these should help in the implementation of quantum computing. A “pea pod” is made up of a tiny carbon nanotube filled with fullerenes, spheres made from carbon atoms. Each sphere contains a nitrogen atom, whose spin then serves as an arithmetic unit. The carbon atoms themselves have no spin and therefore stabilize the nitrogen spin. The “peapods” are placed on a diamond containing nitrogen defects. These can be read out optically and receive spin information from the qubits through coupling.