A Precise Measurement of 87-Rubidium Vector Tune-Out Wavelength

The “tune-out” wavelength of an atomic species corresponds to the frequency of applied light for which the (frequency dependent) AC electric polarizability vanishes. Precise measurements of “tune-out” wavelengths provide valuable knowledge of the species’ transition dipole matrix elements, which are important for a number of experimental and theoretical applications. These include improvements in species-specific optical trapping and aiding atomic parity violation measurements that place valuable constraints on the standard model. The AC polarizability includes scalar, vector and tensor components, so care must be taken to isolate the contribution of interest when performing measurements of the tune-out wavelength. Here we present our recent experimental progress towards a more precise measurement of the 87-Rubidium vector tune-out wavelength lying between the D1 and D2 atomic lines for atoms in the F = 2 hyperfine ground state. These efforts build on our group’s previous work using an atom wave interferometer to measure the scalar portion of the polarizability and aim to improve upon preceding attempts at extracting the vector tune-out wavelength.