Macroscopic magnetic field generated in laser atom interaction

Abstract

We observe shift in the zero magnetic field resonance as the handedness of resonantly interacting circularly polarized light is changed. The characteristic of the shift resembles with the Zeeman light shift that arises due to interaction of non-resonant circularly polarized light with atom. However many attributes of our observed resonant phenomena like dependence on buffer gas, saturation of the shift with light intensity and involved time constant in evolution of the shift contradicts to the fictitious magnetic field model. We propose collective alignment of atomic magnetic moment giving rise to a real magnetic field as a possible mechanism behind the observed shift. The characteristic changes in the signal profile with respect to the three axis magnetic field have been established that can reveal many subtle issues pertaining to the phenomenon.