Abstract
We present the first measurement for helium atoms of the tune-out wavelength at which the atomic polarizability vanishes. We utilize a novel, highly sensitive technique for precisely measuring the effect of variations in the trapping potential of confined metastable () helium atoms illuminated by a perturbing laser light field. The measured tune-out wavelength of compares well with the value predicted by a theoretical calculation [413.02(9) nm] which is sensitive to finite nuclear mass, relativistic, and quantum electrodynamic effects. This provides motivation for more detailed theoretical investigations to test quantum electrodynamics.
- Received 6 March 2015
DOI:https://doi.org/10.1103/PhysRevLett.115.043004
© 2015 American Physical Society