Methods for measuring the electron's electric dipole moment using ultracold YbF molecules

Measurements of the electron's electric dipole moment (eEDM) are demanding tests of physics beyond the standard model. We describe how ultracold YbF molecules could be used to improve the precision of eEDM measurements by two to three orders of magnitude. Using numerical simulations, we show how the combination of magnetic focussing, two-dimensional transverse laser cooling, and frequency-chirped laser slowing, can produce an intense, slow, highly-collimated molecular beam. We show how to make a magneto-optical trap of YbF molecules and how the molecules could be loaded into an optical lattice. eEDM measurements could be made using the slow molecular beam or using molecules trapped in the lattice. We estimate the statistical sensitivity that could be reached in each case and consider how sources of noise can be reduced so that the shot-noise limit of sensitivity can be reached. We also consider systematic effects due to magnetic fields and vector light shifts and how they could be controlled.

Automated summary

Measurements of the electron's electric dipole moment (eEDM) can be significantly improved using ultracold YbF molecules, which can generate precise molecular beams through techniques such as magnetic focussing and laser trapping. Noise reduction and systematic effect control are important considerations in reaching the shot-noise limit of sensitivity for eEDM measurements.