Measurement of the tune-out wavelength for 133Cs at 880nm [dataset]

We perform a measurement of the tune-out wavelength, \lambda_{0}, between the D_{1}, 6^2S_{1/2} --> 6^2P_{1/2}, and D_{2}, 6^2S_{1/2} --> 6^2P_{3/2}, transitions for 133Cs in the ground hyperfine state (F=3, m_{F}=+3). At \lambda_{0}, the frequency-dependent scalar polarizability is zero leading to a zero scalar ac Stark shift. We measure the polarizability as a function of wavelength using Kapitza-Dirac scattering of a 133Cs Bose-Einstein condensate in a one-dimensional optical lattice, and determine the tune-out wavelength to be \lambda_{0}=880.21790(40)_{stat}(8)_{sys} nm. From this measurement we determine the ratio of reduced matrix elements to be |<6P_{3/2}| d|6S_{1/2}>|^{2}/|<6P_{1/2}| d|6S_{1/2}>|^{2}=1.9808(2). This represents an improvement of a factor of 10 over previous results derived from excited-state lifetime measurements. We use the present measurement as a benchmark test of high-precision theory.