Measurement of the 671-nm tune-out wavelength of Li7 by atom interferometry

Abstract

We have measured the tune-out wavelength of lithium isotope 7 Li at 671 nm. We have used our atom interferometer to measure the phase shift due to the dynamical Stark effect as a function of the laser frequency when a laser beam was focused on a single interferometer arm. The tune-out wavelength is a function of the hyperfine F, m F sublevel, and we have prepared the atoms in the sublevel F = 2, m F = +2 or −2. We find that the tune-out frequency of the F = 2, m F = +2 sublevel is at 3388(8) MHz to the blue of the 2 S1/2, F = 1 → 2 P1/2, F = 2 transition, the accuracy of this measurement being limited by imperfect optical pumping. This measurement is in excellent agreement with its theoretical value, and, once corrected for different tensorial contributions, our measurement agrees with the more precise measurement of Copenhaver et al. [Phys. Rev. A 100, 063603 (2019)], who also used atom interferometry but different experimental conditions.

Experimental study of tune-out wavelengths for spin-dependent optical lattice in $^{87}$Rb Bose-Einstein condensation

“…Tune-out wavelengths that ac Stark shift cancels was initially introduced in species-specific optical manipulation [17] and can be useful for optical Feshbach resonances [18] and atomic interferometer [19]. Since tuneout wavelengths are independent of the light intensity [20][21][22], it can be precisely measured by various methods [23][24][25][26][27][28][29][30]. In general, tune-out wavelength is utilized accurately only for the scalar shift by cancelling and neglecting the vector and tensor contribution as much as possible [23][24][25]28].…”

Measurement of the tune-out wavelength for Cs133 at 880 nm

“…Indirect measurements can be made by inferring tune-out wavelengths from measurements of state lifetimes, but can be limited by knowledge of branching ratios [25]. Previous experiments have directly measured tuneout wavelengths, using linearly polarized light, for different alkali-metal atoms, including Li [38,39], K [26,40], and Rb [25,33,37,41], as well as for other atomic species, including He [42], Sr [31], and Dy [43] and also for ground-state NaK molecules [44]. However, despite many theoretical studies of 133 Cs polarizability [45][46][47][48], so far no measurements of 133 Cs scalar tune-out wavelength have been performed.…”

Measurement of the tune-out wavelength for $^{133}$Cs at $880$ nm

“…Indirect measurements can be made by inferring tune-out wavelengths from measurements of state lifetimes, but can be limited by knowledge of branching ratios [25]. Previous experiments have directly measured tune-out wavelengths, using linearly polarized light, for different alkalimetal atoms including Li [38,39], K [26,40], and Rb [25,33,37,41], as well as for other atomic species including He [42], Sr [31], and Dy [43] and also for ground state NaK molecules [44]. However, despite many theoretical studies of 133 Cs polarizability [45][46][47][48], so far no measurements of 133 Cs scalar tune-out wavelength have been performed.…”