Physical Review Letters
Light-force technique for measuring polarizabilities
Michael A. Kadar-Kallen, Keith Bonin
Abstract
We have developed a light-force technique for measuring polarizabilities. This new method uses the polarizaton forces experienced by an atom in the intense, inhomogeneous electric field of a standing-wave laser to deduce the polarizability. Using a Nd:YAG laser at ${\ensuremath{\lambda}}_{\mathrm{SW}}$=1.064 \ensuremath{\mu}m for the light force, we measured the polarizability of rubidium at this wavelength to be \ensuremath{\alpha}(${\mathrm{\ensuremath{\omega}}}_{\mathrm{SW}}$)=114\ifmmode\pm\else\textpm\fi{}9 A${\mathrm{\r{}}}^{3}$ (\ensuremath{\sigma}). Conversion of this ac polarizability to a static value using a semiempirical formula gives a value of ${\mathrm{\ensuremath{\alpha}}}_{\mathrm{dc}}$=52 A${\mathrm{\r{}}}^{3}$, within 10% of the best published experimental results.