Electronic Spectroscopy of YbNH<sub>2</sub> and the Potential for Laser Cooling
YbNH<sub>2</sub> has been recognized as a suitable platform for observations of parity and time-reversal symmetry violations. Gas phase electronic spectra for YbNH<sub>2</sub> were obtained for the <i>Ã</i><sup>2</sup><i>B</i><sub>2</sub>-<i>X̃</i><sup>2</sup><i>A</i><sub>1</sub> and <i>B̃</i><sup>2</sup><i>B</i><sub>1</sub>-<i>X̃</i><sup>2</sup><i>A</i><sub>1</sub> band systems. Both upper states are derived from the Yb<sup>+</sup>(4f<sup>14</sup>6s)NH<sub>2</sub><sup>-</sup> → Yb<sup>+</sup>(4f<sup>14</sup>6p)NH<sub>2</sub><sup>-</sup> electron promotion. Laser excitation and dispersed fluorescence measurements yielded band origins, vibrational constants and rotational band contours. Data for the <i>Ã</i>-<i>X̃</i> system show a Franck-Condon distribution that is favorable for laser cooling. An upper bound for the vibrational branching fraction for the 0<sub>0</sub><sup>0</sup> transition in emission was found to be 0.94, assuming negligible radiation to the low-energy Yb<sup>+</sup>(4f<sup>13</sup>6s<sup>2</sup>)NH<sub>2</sub><sup>-</sup> states. Quantum chemical calculations for the <i>Ã</i>-<i>X̃</i> vibronic bands are reported.
Authors
- Michael C. Heaven (ORCID: https://orcid.org/0000-0003-4738-2408)
- Timothy C. Steimle (ORCID: https://orcid.org/0000-0002-5859-9461)
- Qian Lei (ORCID: https://orcid.org/0000-0001-8647-1011)
- Sophia Vadachkoria
Institutions
- Emory University (US)
- Arizona State University (US)
Publication Details
- Journal
- The Journal of Physical Chemistry Letters
- Published
- 2025-03-25
- DOI
- https://doi.org/10.1021/acs.jpclett.5c00400
- Citations
- 1
- Primary Topic
- Optical properties and cooling technologies in crystalline materials
- Type
- article
- Field-Weighted Citation Impact
- 1.25
Funders
- Division of Chemistry