M-A. Bouchiat

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We have detected, by using stimulated emission, an atomic parity violation (APV) in the form of a chiral optical gain of a cesium vapor on the 7S-6P(3/2) transition, consecutive to linearly polarized 6S-7S excitation. We demonstrate the validity of this detection method of APV, by presenting a 9% accurate measurement of expected sign and magnitude. We(More)
2014 We report Hanle effect measurements of the relaxation in the 7 S1/2 state of cesium by collisions with cesium or buffer gas (helium) atoms in an electric field. The results show the relaxation of the spin polarization to remain isotropic in the adopted configuration, and justify the calibration procedure used in our recent measurements of parity(More)
Laser cooling and trapping offers the possibility of confining a sample of radioactive atoms in free space. Here, we address the question of how best to take advantage of cold atom properties to perform the observation of as highly forbidden a line as the 6S-7S Cs transition for achieving, in the longer term, Atomic Parity Violation measurements in(More)
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 1⁄2 fluorescence intensity and of the probe(More)
A pump-probe atomic parity violation (APV) experiment performed in a longitudinal electric field ~ El, has the advantage of providing a signal which breaks mirror symmetry but preserves cylindrical symmetry of the set-up, i.e. this signal remains invariant when the pump and probe linear polarizations are simultaneously rotated about their common direction(More)
2014 The 6S1/2 8S1/2 caesium transition is excited in a Stark field, with a pulsed narrow-band nitrogenpumped dye-laser. It is detected by monitoring the fluorescence light emitted in the 8S1/2 6P1/2 decay. The scalarto-vector off-diagonal polarizability ratio is obtained : 03B1/03B2 = 4.8 ± 0.5. The M1 amplitude is observed through the electronic(More)
Amplification by stimulated emission of radiation provides an intriguing means for increasing the sensitivity of Atomic Parity Violation (APV) measurements in a pump-probe configuration well adapted to the 6S− 7S cesium transition. It takes advantage of the large number of atoms excited along the path of the pump beam. In the longitudinal Efield(More)
2014 Oddness under reversal of the circular polarization of the exciting light is one important criterion to discriminate the parity violation signal. Imperfections of the polarization flipper or anisotropy in the optical components can generate systematic effects by spoiling the polarization and causing even signals to look partly odd. We discuss the(More)
2014 We have observed the direct single-photon electric dipole excitation of the 7 2S1/2 state of cesium, by exciting the 6 2S1/2 ground state in an external d. c. electric field of 10 to 1 000 V/cm with a single-mode, c. w., tunable dye laser. The resonance was detected by monitoring the decay fluorescence from the excited state. We verified the selection(More)
This paper completes the detailed presentation of our PV experiment on the 6S1/2 7S1/2 transition in Cs. A detailed description of the data acquisition and processing is given. The results of two independent measurements made on 0394F = 0 and 0394F =1 hfs components agree, providing an important crosscheck. After a complete reanalysis of systematics and(More)