Anisotropic dependence of tune-out wavelength near Dy 741-nm transition

TL;DR

This paper measures the anisotropic tune-out wavelength near 741 nm for ground-state bosonic Dy, revealing a strong angular dependence due to tensor polarizability, with implications for precision control of atomic states.

Contribution

First measurement of a Dy tune-out wavelength near 741 nm showing large anisotropy and tunability, expanding understanding of atomic polarizability effects.

Findings

Tune-out wavelength is near 741 nm for $^{162}$Dy.

Strong dependence of the wavelength on the angle between optical field and quantization axis.

Measured wavelengths agree within a few GHz with theoretical calculations.

Abstract

We report the first measurement of a tune-out wavelength for ground-state bosonic Dy and linearly polarized light. The tune-out wavelength measured is near the narrow-line 741-nm transition in $^{162}$Dy, and is the wavelength at which the total Stark shift of the ground state vanishes. We find that it strongly depends on the relative angle between the optical field and quantization axis due to Dy's large tensor polarizability. This anisotropy provides a wide, 22-GHz tunability of the tune-out frequency for linearly polarized light, in contrast to Rb and Cs whose near-infrared tune-out wavelengths do not exhibit large anisotropy. The measurements of the total light shift are performed by measuring the contrast of multipulse Kapitza-Dirac diffraction. The calculated wavelengths are within a few GHz of the measured values using known Dy electronic transition data. The lack of hyperfine structure in bosonic Dy implies that the tune-out wavelengths for the other bosonic Dy isotopes should be related to this $^{162}$Dy measurement by the known isotope shifts.