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arXiv · 1803.03161

Relativistic and QED effects in the fundamental vibration of T$_2$

T. Madhu Trivikram·M. Schlösser·W. Ubachs·E. J. Salumbides
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Abstract

The hydrogen molecule has become a test ground for quantum electrodynamical calculations in molecules. Expanding beyond studies on stable hydrogenic species to the heavier radioactive tritium-bearing molecules, we report on a measurement of the fundamental T$_2$ vibrational splitting $(v= 0 \rightarrow 1)$ for $J=0-5$ rotational levels. Precision frequency metrology is performed with high-resolution coherent anti-Stokes Raman spectroscopy at an experimental uncertainty of $10-12$~MHz, where sub-Doppler saturation features are exploited for the strongest transition. The achieved accuracy corresponds to a fifty-fold improvement over a previous measurement, and allows for the extraction of relativistic and QED contributions to T$_2$ transition energies.

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T. Madhu Trivikram, M. Schlösser, W. Ubachs, E. J. Salumbides. 2018-03-08. Relativistic and QED effects in the fundamental vibration of T$_2$. https://doi.org/10.1103/physrevlett.120.163002

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