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We demonstrate for the first time high-precision differential microwave spectroscopy, achieving sub-Hz precision by coupling a cryogenic buffer gas cell with a tunable microwave Fabry–Perot cavity. We report statistically limited sub-Hz precision of (0.08 ± 0.72) Hz, observed between enantiopure samples of (R)-1,2-propanediol and (S)-1,2-propanediol at frequencies near 15 GHz. We confirm highly repeatable spectroscopic measurements compared to traditional pulsed-jet methods, opening up new capabilities in probing subtle molecular structural effects at the 10−10 level and providing a platform for exploring sources of systematic error in parity-violation searches. We discuss dominant systematic effects at this level and propose possible extensions of the technique for higher precision.
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Nondestructive inelastic recoil spectroscopy of a single molecular ion: A versatile tool toward precision action spectroscopy
We demonstrate a single-molecule technique that is compatible with high-precision measurements and obtain the spectrum of three molecular ion species. While the current result yields a modest spectral resolution due to a broad light source, we expect the method to ultimately provide a resolution comparable to quantum logic methods with significantly less stringent requirements. Adaptations of this technique will prove useful in a wide range of precision spectroscopy arenas including the search for parity-violating effects in chiral molecules.
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- PAR ID:
- 10521725
- Publisher / Repository:
- Physical Review A
- Date Published:
- Journal Name:
- Physical Review A
- Volume:
- 108
- Issue:
- 6
- ISSN:
- 2469-9926
- Subject(s) / Keyword(s):
- spectroscopy molecular ions
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevA.108.062819
