Relativistic study towards photoassociative formation of metastable lanthanide dimers

We theoretically explore the physics behind photoassociative formation of ultracold metastable lanthanide molecules. We are interested in lanthanide atoms and molecules that have a large magnetic moment and electronic orbital angular momentum leading to strong anisotropic interactions between one ground- and one metastable excited-state atom. Expanding the capabilities of our Relativistic Valence-Bond computational suite, we were able to determine that these versatile molecular systems possess key features that do not present in ultracold alkali-metal and alkaline-earth molecules. Here, we investigate how the unique magnetic properties such as the zero-field splitting of paramagnetic dysprosium (DyDy*) and erbium (ErEr*) molecules and strong electric dipole-dipole interaction between colliding atoms could contribute to the photoassociation process.