Strain engineering of the silicon-vacancy center in diamond

Here, the authors tune the color of light emitted by single-atom imperfections (silicon vacancy color centers) inside a diamond. Such tunable imperfections can be networked together to build a quantum internet, where information can be securely exchanged using the laws of quantum physics. One problem is that all the centers need to emit at precisely the same color or wavelength. The authors overcome this challenge by placing color centers inside a diamond nanostring. By adjusting the tension in the string, atoms are stretched inside the crystal and tune the center to emit photons of a desired wavelength. The tuning method involves bending the string with a force controlled handily with an electrical voltage. A symphony of such tunable diamond strings could serve as the backbone of a future quantum internet.