Hanle effect is evidenced in a polarization spectroscopy scheme for the cesium D2 line. The effect is observed in the anisotropy signal for the F = 4 → F′ = 5 hyperfine transition. Results are promising for applications in quantum magnetometry.
We demonstrate polarization spectroscopy of an excited state transition in room temperature cesium vapor. An anisotropy induced by a circularly polarized pump beam on the D2 transition is observed using a weak probe on the 6P3/2 to 7S1/2 transition. When the D2 transition is saturated, a sub-natural linewidth feature is observed which theoretical modeling shows is enhanced by Doppler averaging. Polarization spectroscopy provides a simple modulation-free signal suitable for laser frequency stabilization to excited state transitions.
We demonstrate polarization spectroscopy of an excited state transition in room-temperature cesium vapor. An anisotropy induced by a circularly polarized pump beam on the D2 transition is observed using a weak probe on the 6P(3/2)→7S(1/2) transition. At high pump power, a subfeature due to Autler-Townes splitting is observed that theoretical modeling shows is enhanced by Doppler averaging. Polarization spectroscopy provides a simple modulation-free signal suitable for laser frequency stabilization to excited state transitions.
The problem of the fluorescence anisotropy resulting from alignment in the excited state is investigated in the case of a cesium beam illuminated by a broadband laser diode tuned to the cesium D2 line. Its effect on the collection efficiency is derived when photon fluorescence collection is performed inside a small solid angle about the quantization axis. Excitation schemes leading to a noticeable increase of the fluorescence yield are pointed out and experimental results agree quite well with the predictions.
We demonstrate that the Hanle effect can be tuned between magnetically induced absorption (MIA) and magnetically induced transmission (MIT) simply by changing the polarization of the input laser beam.The experiments are done using closed hyperfine transitions of the D2 line of 133 Cs -Fg = 3 → Fe = 2 and Fg = 4 → Fe = 5.The former shows a transformation from MIT to MIA, while the latter shows the opposite behavior.A qualitative explanation based on optical pumping and coherences among the magnetic sublevels of the ground state is borne out by a detailed density-matrix calculation.To increase the coherence time, the experiments are done in a Cs vapor cell with paraffin coating on the walls.The observed linewidth is extremely narrow (∼ 0.1 mG) compared to previous work in this area, making this a promising technique for all kinds of precision measurements.
We demonstrate that the Hanle effect can be tuned from enhanced absorption to enhanced transmission simply by changing the polarization of the laser beam from linear to circular. The experiments are done on the D2 line of Cs at 852 nm, using the closed hyperfine transition $ F_g = 4 \rightarrow F_e = 5 $. The transformation can be understood qualitatively based on optical pumping and coherences among the magnetic sublevels of the levels involved. To increase the coherence time, the experiments done in a paraffin-coated Cs vapor cell (at room temperature). The observed linewidth is extremely narrow (about 1 mG or 175 Hz), making this a promising technique for all kinds of precision measurements.
We present a theoretical and experimental study of polarization spectroscopy of rubidium atoms. All of the populations of the magnetic sublevels were calculated from the rate equations and used in the calculation of the polarization spectroscopy spectra. Using this model, we could generate theoretical line shapes of the polarization spectra on the D2 transitions of rubidium atoms. The experimental results demonstrated that our model accurately reproduced spectra for all transitions in hyperfine structures.