We employ doubly-resonant two-photon excitation into the 74S Rydberg state to spectroscopically measure the dynamic scalar polarizability, α0, and tensor polarizability, α2, of rubidium 5P 3/2 . To reach the necessary high intensities, we employ a cavity-generated 1064 nm optical-lattice light field, allowing us to obtain intensities near 2 × 10 11 W/m 2 . In the evaluation of the data we use a self-referencing method that renders the polarizability measurement largely free from the intensity calibration of the laser light field. We obtain experimental values α0 = −1149 (±2.5%) and α2 = 563 (±4.2%), in atomic units. Methods and results are supported by simulations.PACS numbers: 32.80. Rm, 37.10.Jk, 32.10.Dk, 37.30.+i Polarizabilities of atomic energy levels govern the response of an atom to an external electric field and are a fundamental property to be considered in atom-trapping and precision-measurement experiments. For example, the polarizabilities are required for determining magic wavelengths of state-insensitive trapping in optical lattices [1,2]. Theoretical calculations of dynamic polarizabilities are complicated, and yet available experimental measurements might carry large uncertainties due to the difficulty in calibrating the field strength experienced by the atoms. Here, we report a measurement of rubidium scalar and tensor polarizabilities conducted in a strong 1064 nm light field, where the magnetic sublevels of Rb 5P 3/2 are resolved and the data analysis is largely free from the calibration of laser intensity. Despite the fact that 1064 nm optical traps for rubidium atoms are widely used in cold-atom trapping, to our best knowledge there is no other such experimental measurement. Our work is not only applicable to experiments utilizing Rb 5P 3/2 levels in 1064 nm laser traps, but also serves as an experimental test for validating and improving existing theoretical models for the polarizability.In the presence of an optical field, an atom is polarized and its energy levels are shifted. The applicable atom- field interaction Hamiltonian,Ĥ E , in a linearly-polarized electric field with amplitude E 0 is(1) where α 0 (ω) and α 2 (ω) are frequency-dependent a.c. scalar and tensor polarizabilities, and J and m J are quantum numbers of the total electronic angular momentum. The dynamic polarizability of the rubidium ground-state 5S 1/2 depends only on α 0 (α 2 is zero because J = 1 2 ). For 5P 3/2 , both α 0 and α 2 contribute to the polarizability. The full Hamiltonian includes the hyperfine structure, H =Ĥ HFS +Ĥ E , witĥwhereÎ is the nuclear spin, A HFS is the magnetic-dipole and B HFS the electric-quadrupole hyperfine constant. A HFS and B HFS are well known for 87 Rb and 85 Rb [3,4]. The octupole contribution is omitted because it is too small to be observed here.We measure α 0 and α 2 using Rydberg two-photon excitation spectroscopy. The data analysis is based on linear fits of spectral data sets in a modified a.c. Stark map, in which the frequencies of the two excitation lasers are plotted a...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.