High precision wavefunctions for hyperfine states of low symmetry materials suitable for quantum information processing

We report on a method of employing spin Hamiltonian data to enhance the accuracy of crystal-field fits for rare-earth impurity sites of low symmetry in crystalline hosts. As an initial test of this method, we apply it to orthorhombic sites in Li+ and Na+ ion charge compensated Sm3+ centers in codoped CaF2 and SrF2 crystals. This yields a good agreement between theory and experiment, in addition to accurately modelling crystal strains due to the differing ionic radii of Li+ and Na+.