Spin-Polarization by Optical Pumping with Selective Reflection

A new optical pumping scheme utilizing selective reflection is proposed and studied for the first time. This method enables us to observe the spin-polarization of atoms even at the high density, at which the pumping beam cannot be transmitted through a sample cell. Theoretical analysis shows that the light reflectivity at the glass-vapor interface is strongly dependent on the direction of the macroscopic magnetic moment of optical pumped atoms. Two types of demonstrating experiments are carried out with Cs and Rb vapors at the temperature - 200°C. In the transverse pumping experiment with a modulated laser beam, asymmetry of the magnetic resonance signal with respect to the inversion of the magnetic field direction is observed as predicted by the theory. In the longitudinal pumping experiment, the transfer of a large amount of the magnetic moment by spin-exchange collisions is directly observed.