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Electronic Spectroscopy of YbNH2 and the Potential for Laser Cooling
Sophia Vadachkoria1, Qingqing Lei1, Timothy C Steimle2
1Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
The Journal of Physical Chemistry Letters
|March 25, 2025
Summary
Ytterbium amide (YbNH2) electronic spectra reveal properties favorable for laser cooling. This research provides crucial data for studying fundamental symmetry violations using YbNH2.
Area of Science:
- Molecular Spectroscopy
- Quantum Chemistry
- Atomic Physics
Background:
- Ytterbium amide (YbNH2) is a promising molecule for detecting parity and time-reversal symmetry violations.
- Understanding its electronic structure is key to utilizing it in precision measurements.
Purpose of the Study:
- To obtain and analyze the gas-phase electronic spectra of YbNH2.
- To investigate the suitability of YbNH2 for laser cooling applications.
- To support experimental efforts with theoretical calculations.
Main Methods:
- Laser excitation spectroscopy.
- Dispersed fluorescence measurements.
- Quantum chemical calculations.
Main Results:
- Electronic spectra for the Ã2B2-X̃2A1 and B̃2B1-X̃2A1 band systems were obtained.
- Band origins, vibrational constants, and rotational contours were determined.
- The Ã-X̃ system exhibits a Franck-Condon distribution favorable for laser cooling, with a high vibrational branching fraction (0.94) for the 000 transition.
Conclusions:
- YbNH2 possesses electronic and spectroscopic properties suitable for laser cooling.
- The obtained spectroscopic data and theoretical calculations provide a foundation for future experiments on symmetry violations.
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