Construction of an apparatus and preliminary measurements for a search for the electric dipole moment of the electron using lead monoxide

We have developed a vapor cell and heater for an experiment to search for an electric dipole moment (EDM) of the electron using the metastable state a(1)[3Σ+] of lead monoxide. Using our apparatus and the method of quantum beat spectroscopy, we have measured the g-factors of the a(1)(3Σ+) state. We obtain (g_∥)₋ = 1.8571 ± 0.0041 for the J = 1− component and ( g_∥)₊ = 1.8584 ± 0.0045 for the J = 1+ component. We also establish a limit on the difference of the g-factors of < 2.3 · 10−3 (90% CL). In the course of our measurements, we have demonstrated shot-noise limited sensitivity to the Zeeman quantum beat frequency of $35HzHz$. We point out relatively straightforward improvements, which should increase the statistical sensitivity to $100mHzHz$ in the near future. With this level of sensitivity, it should be possible to measure an electron EDM of d_e =10−29 e · cm in less than two days.; In a separate set of experiments, we have searched for electronic states with a strong coupling to both the ground state and the a(1)[3Σ +] state, which could be used to improve the excitation and detection efficiency in a future EDM experiment. To this end, we have measured radiative lifetimes and branching ratios for decay through the a(1)[3Σ +] state for most known states of PbO.