Measurement of the scalar third-order electric polarizability of the Cs ground state using coherent-population-trapping spectroscopy in Ramsey geometry

Abstract

The ac-Stark shift induced by blackbody radiation is a major source of systematic uncertainty in present-day cesium microwave frequency standards. The shift is parametrized in terms of a third-order electric polarizability α (3) 0 that can be inferred from the static electric-field displacement of the clock transition resonance. In this paper, we report on an all-optical coherent-population-trapping pump-probe experiment measuring the differential polarizability α (3) 0 = α (3) 0 (F = 4) − α (3) 0 (F = 3) on a thermal Cs atomic beam, from which we infer α (3) 0 (F = 4) = 2.023(6) stat (9) syst Hz/(kV/cm) 2 , which corresponds to a scalar Stark shift parameter k s = −2.312(7) stat (10) syst Hz/(kV/cm) 2 . The result agrees within two standard deviations with a recent measurement in an atomic fountain, and rules out another recent result obtained in a Cs vapor cell.

Spin coherence and optical properties of alkali-metal atoms in solid parahydrogen

“…It is this tensor component which will cause inhomogneous broadening for Larmor precession. The tensor component is zero in second-order perturbation theory, and only appears in third-order perturbation theory including two electric dipole couplings and one hyperfine interaction [40][41][42]. Consequently, we would expect atoms with larger hyperfine splittings to have larger shifts due to their interaction with the matrix.…”

“…dipole couplings and one hyperfine interaction [40][41][42]. Consequently, we would expect atoms with larger hyperfine splittings to have larger shifts due to their interaction with the matrix.…”

Magic wavelengths, matrix elements, polarizabilities, and lifetimes of Cs

“…In 2010, Mitroy et al [11] reviewed the theory and applications of atomic and ionic polarizabilities across the periodic table of the elements. The static and dynamic polarizabilities of Cs have increased in interest recently, as demonstrated by a number of experimental [17][18][19][20][21][22][23][24][25][26][27][28][29] and theoretical [11,[30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] studies.…”

First uncertainty evaluation of the FoCS-2 primary frequency standard

“…where k 0 = −2.282(4) × 10 −10 Hz (V m −1 ) −2 is the DC scalar polarizability of the clock transition [34][35][36][37], E T0 = 831.9 V m −1 is the rms electric field of the BBR at T 0 = 300 K, T F is the average temperature in the free-evolution zone, and = 0.013 ± 0.001 is a numerical coefficient evaluated in [38]. At METAS, the FoCS-2 primary standard is located in a temperature-controlled laboratory with the temperature maintained at 295.30 K with annual peak-to-peak variations on the order of 0.15 K (figure 14).…”