Saturated absorption spectroscopy in the presence of a longitudinal magnetic field

V. P. Mishchenko

А. П. Войтович, Alexei P. Shkadarevich

Un Yob Shim, Jong-An Kim, W. Jhe

Recently a new type of spectroscopy using Zeeman shift has been developed, which aims for a large recapture range by making a dispersive-like signal obtained from the subtraction of two different circularly polarized Doppler-broadened absorption signals in the presence of a magnetic field (order of 100 G). We would like to propose another method for stabilizing a diode laser frequency onto an atomic frequency with a small tunable range in the presence of small longitudinal magnetic field (order of Gauss). A solid state diode laser is preferred as it is a good light source. Our technique has the advantages of cancellation of frequency fluctuation over side-locking and no need for phase-sensitive detection and frequency modulation over peak-locking. A subtracted SAS signal and the blocking signal are displayed on one photodiode.

Armen D. Sargsyan, Rodolphe Momier, Claude Leroy +1 more

Abstract It is demonstrated that the use of a micrometric thin 39 K vapor cell (MTC) and saturated absorption (SA) spectroscopy allows the formation of narrow atomic lines in the transmission spectrum without unwanted cross-over resonances. Another important feature is the small characteristic magnetic field value B 0 = A h f / μ B of 39 K, significantly smaller than for Rb and Cs. As a consequence, decoupling of J and I can be observed at relatively low magnetic fields ∼300 G, which results in the formation of two groups of four spectrally-resolved and equidistantly-positioned atomic transitions having the same amplitude (each group corresponds to a given circular polarization σ ± ) which we record using a simple experimental setup with a linearly polarized tunable diode-laser and a longitudinal magnetic field obtained with two permanent magnets. Fabrication of a MTC is much easier than the fabrication of the 39 K nanocells used in our previous works. A simple method to determine the magnitude of a wide range of B -fields with a spatial resolution of 30 µ m is presented, which is intrinsically calibrated and does not require a frequency reference.

W. K. Hensinger, Andrew G. Truscott, Halina H. Rubinsztein-Dunlop +1 more

I. A. Kartashov, А. А. Черненко, A. V. Shishaev

We have studied experimentally and theoretically the shapes of spectropolarimetric resonances of a linearly polarized probe wave for the transitions 1s 5-2p 2 and 1s 5-2p 4 in the neon atom in the presence of a strong counterpropagating circularly polarized wave of the same frequency. Physical processes that lead to a change in the shape of polarimetric resonances under the action of a longitudinal magnetic field have been determined.