Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Measurement method for the nuclear anapole moment of laser-trapped alkali-metal atoms

E. Gómez, S. Aubin, Gene D. Sprouse, Luis A. Orozco, David P. DeMille

Published Mar 27, 2007• 53 citations
Publisher

Abstract

Weak interactions within a nucleus generate a nuclear spin dependent, parity-violating electromagnetic moment, the anapole moment. We analyze a method to measure the nuclear anapole moment through the electric dipole transition it induces between hyperfine states of the ground level. The method requires tight confinement of the atoms to position them at the antinode of a standing wave Fabry-Perot cavity driving the anapole-induced microwave $E1$ transition. We explore the necessary limits in the number of atoms, excitation fields, trap type, interrogation method, and systematic tests necessary for such measurements in francium, the heaviest alkali.

DOI
10.1103/physreva.75.033418

Related papers

Atomic Parity Nonconservation Experiment

Pintu Mandal

Motivated by the challenges and limitation of existing experimental techniques, this work elaborates our recent proposal for the precision measurement of atomic parity nonconservation by quantum metrology with an entangled pair of trapped ions. Although the technique is fundamentally based on an existing proposal, it can potentially reach a figure of merit twice as high for an exceedingly tiny observable, yet to be measured in any ion trap experiment. The systematic of the technique have been shown to be better controlled as compared to other experiments. Since the goal of the experiment is to test the Standard Model of physics, the measured parity violating transitional dipole matrix element has to be compared with the theory of competitive precision. The choice of the element therefore plays an important role for the success of the experiment. Barium and radium ions have been compared from this perspective. The work presents the theoretical study on nuclear spin dependent atomic parity nonconservation and nuclear anapole moment in different isotopes of these ions and proposes specific transitions that are experimentally feasible.

•Mar 18, 2014•0 citations

Trapping of francium for parity violation experiments

S. Aubin, E. Gómez, Joshua M. Grossman +2 more

Summary form only given. We have constructed a new apparatus for producing and on-line trapping of francium for parity non-conservation experiments. At present, we have produced and delivered 15 /spl times/ 10/sup 6/ Fr/sec to the trapping area with better than 90% efficiency. The electrostatic optics of our beamline ensure mass independent transport of all francium isotopes and even other alkalis, such as rubidium, which we use for testing most of our apparatus. After accumulation in this first MOT, we transfer the atoms to a second MOT in a separate vacuum chamber one meter below, where they are transferred to a far off-resonance optical dipole trap for PNC experiments. At present, we are constructing the apparatus for a measurement of the PNC anapole moment by probing the microwave E1 transition between the ground state hyperfine levels of francium.

Quantum Electronics and Laser Science Conference•Jun 25, 2003•0 citations

Preliminary studies for anapole moment measurements in rubidium and francium

D Sheng, Luis A. Orozco, E. Gómez

Preparations for the anapole measurement in Fr indicate the possibility of performing a similar measurement in a chain of Rb. The sensitivity analysis based on a single nucleon model shows the potential for placing strong limits on the nucleon weak interaction parameters. There are values of the magnetic fields at much lower values than found before that are insensitive to first order changes in the field. The anapole moment effect in Rb corresponds to an equivalent electric field that is eighty times smaller than Fr, but the stability of the isotopes and the current performance of the dipole trap in the apparatus, presented here, are encouraging for pursuing the measurment.

arXiv:1001.0817•Journal of Physics B Atomic Molecular and Optical Physics•Mar 19, 2010•32 citations

Anapole moments and magnetic fields in alkali-metal atoms from Stark mixing

A. Bhattacharya, B. Talukdar

Toroidal dipole (anapole) moments and magnetic fields due to inversion symmetry breaking by an external electric field are studied for the alkali-metal atoms from Li to Rb. It is demonstrated that a hydrogenic atomic model is inadequate for this purpose, while a nonhydrogenic model based on the quantum-defect method yields numbers for the anapole moments in excellent agreement with those predicted by a semiempirical product rule.

Physical Review A•Jan 13, 2000•1 citation

First Measurement of the Atomic Electric Dipole Moment of $^{225}$Ra

Richard H. Parker, Matthew Dietrich, Kalita, M. R. +10 more

The radioactive radium-225 ($^{225}$Ra) atom is a favorable case to search for a permanent electric dipole moment (EDM). Due to its strong nuclear octupole deformation and large atomic mass, $^{225}$Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique to study the spin precession of $^{225}$Ra atoms held in an optical dipole trap, and demonstrated the principle of this method by completing the first measurement of its atomic EDM, reaching an upper limit of $|$$d$($^{225}$Ra)$|$ $

arXiv:1504.07477•Apr 28, 2015•7 citations

Macroscopic amplification of electroweak effects in molecular Bose-Einstein condensates

Pedro Bargueño, Fernando Sols

We investigate the possible use of Bose-Einstein condensates of diatomic molecules to measure nuclear spin-dependent parity-violation effects, outlining a detection method based on the internal Josephson effect between molecular states of opposite parity. When applied to molecular condensates, the fine experimental control achieved in atomic bosonic Josephson junctions could provide data on anapole moments and neutral weak couplings.

arXiv:1202.2971•Physical Review A•Feb 17, 2012•5 citations
Weak interactions within a nucleus generate a nuclear spin dependent, parity-violating electromagnetic moment, the anapole moment. We analyze a method to measure the nuclear anapole moment through the electric dipole transition it induces between hyperfine states of the ground level. The method requires tight confinement of the atoms to position them at the antinode of a standing wave Fabry-Perot cavity driving the anapole-induced microwave E1E1E1 transition. We explore the necessary limits in the number of atoms, excitation fields, trap type, interrogation method, and systematic tests necessary for such measurements in francium, the heaviest alkali.
Motivated by the challenges and limitation of existing experimental techniques, this work elaborates our recent proposal for the precision measurement of atomic parity nonconservation by quantum metrology with an entangled pair of trapped ions. Although the technique is fundamentally based on an existing proposal, it can potentially reach a figure of merit twice as high for an exceedingly tiny observable, yet to be measured in any ion trap experiment. The systematic of the technique have been shown to be better controlled as compared to other experiments. Since the goal of the experiment is to test the Standard Model of physics, the measured parity violating transitional dipole matrix element has to be compared with the theory of competitive precision. The choice of the element therefore plays an important role for the success of the experiment. Barium and radium ions have been compared from this perspective. The work presents the theoretical study on nuclear spin dependent atomic parity nonconservation and nuclear anapole moment in different isotopes of these ions and proposes specific transitions that are experimentally feasible.
Summary form only given. We have constructed a new apparatus for producing and on-line trapping of francium for parity non-conservation experiments. At present, we have produced and delivered 15 /spl times/ 10/sup 6/ Fr/sec to the trapping area with better than 90% efficiency. The electrostatic optics of our beamline ensure mass independent transport of all francium isotopes and even other alkalis, such as rubidium, which we use for testing most of our apparatus. After accumulation in this first MOT, we transfer the atoms to a second MOT in a separate vacuum chamber one meter below, where they are transferred to a far off-resonance optical dipole trap for PNC experiments. At present, we are constructing the apparatus for a measurement of the PNC anapole moment by probing the microwave E1 transition between the ground state hyperfine levels of francium.
Preparations for the anapole measurement in Fr indicate the possibility of performing a similar measurement in a chain of Rb. The sensitivity analysis based on a single nucleon model shows the potential for placing strong limits on the nucleon weak interaction parameters. There are values of the magnetic fields at much lower values than found before that are insensitive to first order changes in the field. The anapole moment effect in Rb corresponds to an equivalent electric field that is eighty times smaller than Fr, but the stability of the isotopes and the current performance of the dipole trap in the apparatus, presented here, are encouraging for pursuing the measurment.
First Measurement of the Atomic Electric Dipole Moment of 225^{225}225Ra
The radioactive radium-225 (225^{225}225Ra) atom is a favorable case to search for a permanent electric dipole moment (EDM). Due to its strong nuclear octupole deformation and large atomic mass, 225^{225}225Ra is particularly sensitive to interactions in the nuclear medium that violate both time-reversal symmetry and parity. We have developed a cold-atom technique to study the spin precession of 225^{225}225Ra atoms held in an optical dipole trap, and demonstrated the principle of this method by completing the first measurement of its atomic EDM, reaching an upper limit of ∣|∣ddd(225^{225}225Ra)∣|∣ $