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arXiv · 1710.04378

Tuning of the Hanle effect from EIT to EIA using spatially separated probe and control beams

Mangesh Bhattarai·Vineet Bharti·Vasant Natarajan
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Abstract

We demonstrate a technique for continuous tuning of the Hanle effect from electromagnetically induced transparency (EIT) to electromagnetically induced absorption (EIA) by changing the polarization ellipticity of a control beam. In contrast to previous work in this field, we use spatially separated probe and control beams. The experiments are done using magnetic sublevels of the $ F_g = 4 \rightarrow F_e = 5 $ closed hyperfine transition in the 852 nm D$_2$ line of $^{133}$Cs. The atoms are contained in a room temperature vapor cell with anti-relaxation (paraffin) coating on the walls. The paraffin coating is necessary for the atomic coherence to be transported between the beams. The experimental results are supported by a density-matrix analysis of the system, which also explains the observed amplitude and zero-crossing of the resonances. Such continuous tuning of the sign of a resonance has important applications in quantum memory and other precision measurements.

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Mangesh Bhattarai, Vineet Bharti, Vasant Natarajan. 2017-10-12. Tuning of the Hanle effect from EIT to EIA using spatially separated probe and control beams. https://doi.org/10.1038/s41598-018-25832-8

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