Lanthanide dopants in oxide hosts provide excellent spin-photon interfaces for quantum technologies, including by mediating microwave to optical quantum transduction (converting a collective spin excitation to an optical excitation), and for quantum memories. The description of magnetic dipole transitions in lanthanides using model Hamiltonians principally relies on existing experimental fit parameters for terms in the Hamiltonian like the effect of the crystal field on the 4f elections. 1
Here, we deploy an ab initio extraction of crystal field parameters explored by Dadi Dai et al. 2 With ab initio, we extracted crystal field parameters in Er defects in hosts like Y2O3, and in combining the extracted crystal field parameters with the effective operator Hamiltonian approach we were able to compare the theoretical crystal field energy correction with experimental values directly and obtained a relatively good match. In further studies we’re exploring a more systematic prediction of crystal field levels to pave the path for a wide search of lanthanide doped spin-photon systems.

We acknowledge funding from NSF DMR-1921877.