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arXiv · 1505.03642

Precision Measurement for Metastable Helium Atoms of the 413 nm Tune-Out Wavelength at Which the Atomic Polarizability Vanishes

B. M. Henson·R. I. Khakimov·R. G. Dall·K. G. H. Baldwin·Li-Yan Tang·A. G. Truscott
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Abstract

We present the first measurement for helium atoms of the tune-out wavelength at which the atomic polarizability vanishes. We utilise a novel, highly sensitive technique for precisely measuring the effect of variations in the trapping potential of confined metastable ($2^{3}S_{1}$) helium atoms illuminated by a perturbing laser light field. The measured tune-out wavelength of 413.0938($9_{Stat.}$)($20_{Syst.}$) nm compares well with the value predicted by a theoretical calculation (413.02(9) nm) which is sensitive to finite nuclear mass, relativistic, and quantum electro-dynamic (QED) effects. This provides motivation for more detailed theoretical investigations to test QED.

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B. M. Henson, R. I. Khakimov, R. G. Dall, K. G. H. Baldwin, Li-Yan Tang, A. G. Truscott. 2015-05-26. Precision Measurement for Metastable Helium Atoms of the 413 nm Tune-Out Wavelength at Which the Atomic Polarizability Vanishes. https://doi.org/10.1103/physrevlett.115.043004

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