Search for EDM of ultra-cold neutral atoms

I report on our project of measuring a permanent electric dipole moment of atomic ytterbium using laser cooling and trapping method. This will reduce the experimental limit below the best achieved so far by exploiting the following features of trapped atoms: low magnetic field, possibility of applying large external electric field, large density of atoms and low inhomogeneity of external field in the measurement region, and lack of frequency-shifting and -broadening at ultracold collisions. This could have a profound impact on particle physics and possibly open a new way to physics beyond the Standard Model. In this paper, I describe our experimental efforts toward this goal, and new methods for further increasing the EDM sensitivity. (author)