Fig 6 - uploaded by Martial Ducloy
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Illustration of the simulation of the fluorescence spectrum for (a) ν 4 and (b) ν 3 transitions. Vertical bars show the relative strength of the individual fluorescence components |F e m〉 |F g µ〉 for B = 0 (upper row) and |γ k m〉 |η j µ〉 for B = 55 Gauss,
Source publication
The fluorescence spectra of a submicron atomic cesium vapor layer observable under resonant excitation on the D2 line are studied in the presence of an external magnetic field. Substantial changes in the amplitudes and frequency positions of individual hyperfine transitions (resolved using a 300-nm-long vapor cell) were recorded in moderate magneti...
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Context 1
... light polarization, then we must simply take the sum of two fluorescence com- ponents with orthogonal polarizations observed in a definite direction and the sum of two spectral transi- tions to both the ground-state hyperfine levels with F g = 3 and F g = 4. Such a simulated spectrum for lin- early and circularly polarized excitation is given in Fig. 6. The left and right graphs of the upper rows refer to the absorption of linearly and circularly polarized ...
Context 2
... linewidth (natural and col- lisional), and residual Doppler broadening. Of course, when we have a homogeneous linewidth combined with inhomogeneous broadening, the resulting line shape should be a Voigt contour, but, in order to make the model as simple as possible, the Lorentz-type line shape for each individual peak was chosen for produc- ing Fig. 6. This assumes that the remaining Doppler broadening is smaller than the homogeneous ...
Context 3
... ⋅ which the absorption started. In the lower row graphs in Fig. 6, the fluorescence spectra (line positions and rela- tive intensities) are shown as vertical bars for the case of excitation from F g = 4 (a) and F g = 3 (b) with linear and circular light polarization. The dashed lines again show the resulting spectra, supposing that each compo- nent has a Lorentz line shape with 55 MHz in width. The ...
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We demonstrate an atomic bandpass optical filter with an equivalent noise bandwidth less than 1 GHz using the D 1 line in a cesium vapor. We use the ElecSus computer program to find optimal experimental parameters and find that, for important quantities, the cesium D 1 line clearly outperforms other alkali metals on either D-lines. The filter simul...
Citations
... where E 0 (F ) is the initial energy [109] of the sub-level |n, L, J, F, m F ≡ |F, m F and g F is the effective Landé factor [109]. ...
... where E 0 (F ) is the initial energy [109] of the sub-level |n, L, J, F, m F ≡ |F, m F and g F is the effective Landé factor [109]. ...
Using a narrow-band resonant fluorescence spectra from a nano-cell with a thickness of L= [lambda]/2, and VSOP resonances formed at a thickness L =[lambda] ([lambda] is the wavelength of the resonant radiation), for the first time it was experimentally investigated the behaviour of the frequency and intensity (transition probabilities) of the atomic hyperfine structure transitions between the 85Rb, 87Rb, D1 and D2 lines Zeeman sublevels in external magnetic fields in range 5 - 7000G. The behaviour of tens of previously unstudied atomic transitions was analyzed and it is demonstrated that the intensities of these lines can both greatly increase, and decrease (tenfold). For the first time it is demonstrated that, in the case of partial pressure of neon buffer gas up to 6~torr into the nano-cell of thickness L = [lambda] filled with Rb, VSOP resonances are recorded confidently, while the addition of 0.1~torr neon buffer gas in a cell of a centimeter thickness leads to the complete disappearance of VSOP resonances formed with the help of the widely used technique of saturated absorption. It is demonstrated for the first time that the spectral width of the resonant fluorescence spectra of the rubidium nano-cell with thickness L= [lambda]/2, for all values of the neon buffer gas pressures is much narrower (6-8 times) compared with the resonant fluorescence spectra of an ordinary centimeter cell containing rubidium with the same pressures of neon
... In Sections 2-4 we describe a technique based on the use of spectrally-narrow (close to natural linewidth) velocity selective optical pumping/saturation (VSOP) resonances peaks, which appear at laser intensities 1 mW/cm 2 exactly at the positions of atomic transitions in the transmission spectrum of the nanocell with the Rb atomic vapor column thickness of L = ( being the wavelength of laser radiation resonant with Rb D 1 or D 2 atomic lines, 794 or 780 nm) 3,[12][13][14][15][16][17] . Each VSOP resonance is split in an external magnetic field into several Zeeman components, the number of which depends on the quantum numbers F of the lower and upper levels 7,9,10,18 . The amplitudes of these components and their frequency positions depend unambiguously on B-field. ...
... Here the examination of the VSOP resonances formed in a nanocell allowed us to obtain, identify, and investigate the atomic transitions between the Zeeman sublevels in the transmission spectrum of the 87 Rb D 2 line in the range of magnetic fields 0.5 22 mT, i.e., the transitions F g =1 F e =0,1,2 (as well as "forbidden" F g =1 F e =3) for + (left circular) and (right circular) polarizations of the exciting laser radiation. We studied experimentally the atomic transitions, for which the selection rules Figure 3 shows the theoretical values of frequency positions of atomic transitions between Zeeman sublevels (VSOP resonances in our case) for 87 Rb D 2 line hfs F g =1 F e =0,1,2,3 components for + -laser polarization depending on the strength of the external magnetic field; the data are obtained with the model developed in 5,6,10,18 . This figure enables one to determine the frequency shift of atomic transitions from their initial positions in zero magnetic field; this shift is reckoned from the transition F g =1 F e =2 (for B 0), which is suitable for comparison with the experiment. ...
... Application of a longitudinal magnetic field modifies the spectrum shape and causes an overall frequency shift, dependent on sign and magnitude of the B-field (see Fig.14). This behavior linked with magnetic circular dichroism exhibited for circular polarization of laser field was qualitatively expected 10,18 . We emphasize this peculiarity as promising feature for tuning the locked laser radiation frequency. ...
Sub-Doppler nature of atomic spectra in alkali metal vapor cells of nanometric thickness L (nanocells) allows one to study peculiarities of magneto-optical processes, which occur in a magnetic field for the case when L is of the order of lambda (lambda is a laser resonant wavelength). We particularly address the issues of practical implementation of the studied processes. The following results are presented. i) A "lambda-Zeeman technique" exploiting velocity-selective optical pumping resonances in L = lambda Rb cell placed in a B-field, which allows direct determination frequency shifts and modification of transition probabilities of individual Zeeman transitions in magnetic field and is applicable for development of wide-range (~ 0.1 - 1000 mT) optical magnetometers and tunable frequency reference. ii) A technique for locking the laser radiation frequency, B-field-tunable in ~ 500 MHz range, which is based on selective reflection of a circularly-polarized laser beam from Rb vapor cell with thickness L ≈ lambda/2.
Interaction of alkali atoms with external magnetic field induced a splitting and a shift of their energy levels. We have studied this interaction for external field from 0 to 5000 Gauss when the alkali vapor is confined in submicron thin vapor cell with thickness L = lambda /2. Rubidium and Sodium vapors have been studied. The Hamiltonian can be expressed as the sum of the unperturbated atomic Hamiltonian and the so-called Zeeman Hamiltonian. The probability of a transition, induced by the laser electric field is proportional to the square of the transfer coefficients modified by the presence of the magnetic field. We will show that the strong nonlinearity of the transition intensities versus the external magnetic field intensity is obvious for B > 100 G. Some possible applications for Laser Spectroscopy of the Rb and the Na atoms are presented.
It is experimentally demonstrated that use of an extremely thin cell (ETC) with the thickness of a Rb atomic vapor column of 400 nm allows one to resolve a large number of individual transitions between Zeeman sub-levels of the D 1 line of 87 Rb and 85 Rb in the sub-Doppler fluorescence excitation spectra in an external mag-netic field of 200 G. It is revealed that due to the peculiarities of the Zeeman effect for different hyperfine levels of Rb, all allowed transitions between magnetic sublevels can be clearly resolved for 87 Rb F g 1 → F e 1, 2 and F g 2 → F e 1, 2 fluorescence excitation. Also, relatively good spectral resolution can be achieved for 85 Rb F g 2 → F e 2, 3 fluorescence excitation. Some partial resolution of transitions between magnetic sublevels is achieved for 85 Rb F g 3 → F e 2, 3 fluorescence excitation. The spectral resolution of individual transitions allows one to easily observe both linear and nonlinear Zeeman effects in the fluores-cence excitation spectra obtained with the help of the ETC. In the fluorescence spectra of a cell of usual length there is no evidence of a spectral resolution of individual transitions at B 200 G. A simple magnetometer based on ETC with Rb with a submicrometer spatial resolution is described.
