Transition Probabilities for z-Polarized Light

Alexander V. Glushkov, A. V. Tarchenko

M. G. Veselov

Matthew Fewell

The theory of the incoherent absorption of light by quantum systems is examined to determine how the transition probabilities of the substates of an initial energy level vary as the polarization of the exciting radiation is altered. The aim is to identify polarizations for which the spread of transition rates among the substates of an energy level is a minimum. To achieve this, a new set of quantization axes is proposed for the case of elliptical polarization. The definition of these new axes is based on a consideration of Poincare's sphere. As the polarization is varied, the axes move smoothly between the sets of axes conventionally used for linear and circular polarization. Using these axes, expressions are derived for the transition probability for the absorption of a photon of specified polarization by a specified substate of the initial level. This expression applies to any multipolarity of transition and covers the case of partial polarization.

Dixith Manchaiah, Rohit Kumar, Raghavan K. Easwaran

Abstract We investigate both experimentally and theoretically the cascade electromagnetically induced transparency (EIT) in 5 S 1 / 2 − 5 P 3 / 2 − 5 D 5 / 2 configuration in 87Rb atomic vapor medium in the presence of vortex coupling Laguerre Gaussian (LG) light. We demonstrated Doppler free double resonance EIT structure in cascade configuration and observed transmission spectra for | H ⟩ − | H ⟩ and σ + − σ + polarized probe and coupling lights. We demonstrate that the double resonance structure can be identified by two photon transition probabilities and it is found to be F ′ ′ = 2 and F ′ ′ = 3 . By considering coupling LG light, several polarization combinations are taken into account, and their effects on amplifying and diminishing the EIT resonances are demonstrated experimentally. In order to understand the polarization effects of vortex coupling light on EIT spectrum in a degenerate multilevel atomic system, a theoretical model is developed by considering a simplified double hut level structure. Semi-classical density matrix analysis is used to understand the dynamics and also to establish the enhancement and reduction of EIT peak height with coupling light polarizations. The impact of two photon transition probabilities, polarization combinations and relative orientations of probe and coupling lights in degenerate multilevel atomic systems leads to modification of EIT resonances significantly. We establish quantitative agreement between our theory and experimental results.

A. Assfalg, Jochen Fricke, J. Haas +2 more

Abstract The 6 S5/2 ground state of Mn 55 was polarized by spin exchange collisions with an optically pumped Cs-vapour. The rf induced transitions between Zeeman subleves of Mn were detected as a change in the Cs pumping light transmission. To estimate the effectiveness of direct optical pumping or of detection with resonance light the absorption probabilities for circlarly polarized light are given as functions of 〈Sz〉.