Observation and optimization of DAVLL spectra on the 1S0–3P1 transition of neutral mercury atom

The dichroic atomic vapor laser locking (DAVLL) spectra on the 1S0–3P1 transition of neutral mercury atoms are reported for the first time. Two classes of DAVLL line shapes corresponding to single resonant transition and the combinations of several transitions are experimentally observed and compared with numerical simulation. The dependences of peak-to-peak amplitude and the slope near the zero-crossing point on the axial magnetic field and cell temperature are also investigated. A simple model was introduced to briefly estimate the optimal magnetic field with the largest slope. The optimal operating parameters in a 1 mm cell are highlighted to use DAVLL to lock the frequency of the 253.7 nm UV trap laser of mercury atoms.