In a diamond crystal, a tiny defect sometimes occurs: a nitrogen atom takes the place of a carbon atom, and nearby a lattice site is empty. Electrons in this spot behave like a spinning top that can rotate in different directions. These 'spinning tops' are ready-made cells for future quantum computers and ultra-sensitive sensors.

But to assemble a device from them, you need to know in advance how they will affect each other. A classical computer quickly gets bogged down in calculations: too many particles, too many interactions. The authors of the study propose assigning this task to a quantum computer. They wrote a program that can compress the description of the system and speed up calculations, saving up to a third of operations.

Testing on a real example, a nitrogen vacancy in diamond, showed that calculations on a quantum computer match classical ones but open the way to more complex systems. Thus, the quantum computer becomes a drawing board for the materials of the future.