An improved measurement of the electron electric dipole moment (EDM) appears feasible using groundstate alkali atoms in an atomic fountain in which a strong electric field, which couples to a conceivable EDM, is applied perpendicular to the fountain axis. In a practical fountain, the ratio of the atomic tensor Stark shift to the Zeeman shift is a factor μ ~ 100.We expand the complete time-evolution operator in inverse powers of this ratio; complete results are presented for atoms of total spin F = 3, 4, and 5. For a specific set of entangled hyperfine sublevels (coherent states), potential systematic errors enter only as even powers of 1/μ, making the expansion rapidly convergent. The remaining EDM-mimicking effects are further suppressed in a proposed double-differential setup, where the final state is interrogated in a differential laser configuration, and the direction of the strong electric field also is inverted. Estimates of the signal available at existing accelerator facilities indicate that the proposed apparatus offers the potential for a drastic improvement in EDM limits over existing measurements, and for constraining the parameter space of supersymmetric (SUSY) extensions of the Standard Model.
B. J. Wundt et al., "Quantum Dynamics in Atomic-Fountain Experiments for Measuring the Electric Dipole Moment of the Electron with Improved Sensitivity," Physical Review X, vol. 2, no. 4, pp. 041009-1-041009-25, American Physical Society (APS), Nov 2012.
The definitive version is available at https://doi.org/10.1103/PhysRevX.2.041009
Keywords and Phrases
Alkali Atoms; Atomic Fountains; Coherent State; Electron Electric Dipole Moment; Final State; Hyperfines; Laser Configuration; Parameter Spaces; Quantum Dynamics; Stark Shift; Strong Electric Fields; The Standard Model; Time Evolutions; Zeeman Shift; Electric Fields; Fluorine; Fountains; Quantum Entanglement
International Standard Serial Number (ISSN)
Article - Journal
© 2012 American Physical Society (APS), All rights reserved.
01 Nov 2012