Accurate hyperfine tensors for solid state quantum applications: case of the NV center in diamond

The decoherence of point defect qubits is often governed by the electron spin–nuclear spin hyperfine interaction that can be parameterized by ab initio calculations. Most theoretical works have focused on the closest nuclear spins, while the accuracy for more distant nuclei is rarely discussed. For the NV center in diamond, the absolute relative error of computed hyperfine parameters can exceed 100% using an industry standard first-principles code. To overcome this, an alternative method is implemented that yields significantly improved hyperfine values with about 1% relative mean error at all distances. The accurate hyperfine data for the NV center enables high-precision simulation of NV quantum nodes for quantum information processing and positioning of nuclear spins by comparing experimental and theoretical hyperfine data.

István Takács, Viktor Ivády