The Cs 6S-7S-6P3/2 forbidden three-level system : analytical description of the inhibited fluorescence and optical rotation spectra

Abstract

En vue d'améliorer la précision des mesures de violation de parité dans le césium, nous avons étudié le « système interdit à trois niveaux » 6S-7S-6P3/2, dans lequel un premier laser excite la transition interdite 6S-7S pendant qu'un deuxième faisceau, colinéaire au premier, sonde les atomes excités dans le niveau 7S. Dans cet article, nous présentons un calcul analytique de la fluorescence du niveau 7S, ainsi que de l'amplification du faisceau sonde, en fonction des fréquences des lasers. Nous prenons en compte les collisions dans le niveau de résonance 6P3/2, ainsi que la multiplicité des niveaux et les polarisations des lasers. L'accord quantitatif avec l'expérience est satisfaisant ; les spectres sans effet Doppler sont correctement décrits. Nous obtenons les amortissements de la cohérence 7S-6P3/2 et de la population emprisonnée dans 6P3/2. Nous présentons de nouveaux procédés de détection de l'orientation du niveau 7S, qui doivent pouvoir être étendus directement à la détection d'un alignement. Abstract.-With a view to improved parity violation measurements in Cs, we have considered the 6S-7S-6P3/2 « forbidden three-level system », in which one laser excites the forbidden 6S-7S transition while a second, colinear laser probes the excited 7S atoms. This paper presents an analytical calculation of the 7S ~ 6P ½ fluorescence intensity and of the probe amplification as functions of the laser frequencies. The collisional processes in the 6P3/2 resonance level, as well as the level multiplicity and the laser polarizations are taken into account. The quantitative agreement with experiment is good ; in particular, the observed sub-Doppler structures are correctly described. The damping rates of the 7S-6P3/2 cohérence and of the trapped 6P3/2 atoms are extracted. New détection schemes for detecting a 7S orientation, with direct possible extension to an alignment, are demonstrated.

Measurement of the parity violating6S−7Stransition amplitude in cesium achieved within2×10−13Guéna1, Lintz2, Bouchiat3 2005Phys. Rev. ASelf Cite903660View full textAdd to dashboardCite

“…For example for the realistic values γ d t p = 1.49, and A ⊥ (E l ) = 0.68, we obtain ǫ = 0.100. The precision in ǫ is limited by the uncertainty on γ d , itself a linear function of the cesium atomic density [47]. Allowing for 5% uncertainty on this latter, hence 3% one on γ d , the resulting uncertainty on E exp l is 0.3%.…”

Measurement of the radiative lifetime of the cesium 5D5/2 level using pulsed excitation and delayed probe absorption

“…The solid line shows the least-squares fit by the function K [ -exp ( -r / T D ) + exp ( -r / Tp)] which involves the lifetimes TD and Tp of the 5D5/2 and 6P3/2 levels respectively. The value of T e, two orders of magnitude larger than the radiative lifetime, results from resonance radiation trapping and has already been measured in CW experiments [13]. Conscious that the decay of the 6P population may depart from an exact exponential if the diameters of the excited and probed regions are very different [ 14], we have varied the parameters that determine the conditions of the trapping, that is, the radii of the kt- The 6P~/2-+6pv z collisional transfer cross-section [9] is too small to give a significant amount of 6P3/2 atoms for the Cs densities at which we operate beams (from 0.5 to 2 mm) and the Cs density (from 0.9 to 2.2 × 10 I4 at.cm-3).…”

Amplification of electroweak left-right asymmetry in atoms by stimulated emission

“…where we have dropped all dependence upon y and m. The rate 2~ = N6~(v~)o-~ can be shown to coincide with 2~ = 2TZ 1 in the limit T2 ~ rTS, z6p~ [21]. Integrating the differential equation given in equation (A.2) with the boundary condition AN6e3,~ = AoN6p~ for t = 0, one gets for t >> T2:…”