Orchestrating optical pumping with magnetic field for enhanced magnetometry

The atomic population trapped in uncoupled atomic states is a limiting factor for processes based on laser-atom interaction. The use of repump laser, bi-chromatic field, and vector magnetic field are explored in degenerate as well as non-degenerate atomic system to overcome the limitation. The magnetic resonance of 85Rb atoms under these complementary conditions are investigated in a buffer gas filled cell. The most suitable condition is achieved by the combined action of a bi-chromatic light with a specific combination of magnetic fields for non-degenerate levels where the relevant magnetic resonance shows more than 7-fold increase in its amplitude. The phenomenon is consistently observed through RF as well as magnetic field de-modulation technique. It will lead to similar improvement in the sensitivity of the atomic magnetometers. The optical pumping of the atomic population to the stretch state by manipulation of magnetic field will be of general interest involving quantum technology.