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Identifying single molecular ions by resolved sideband measurements
James E Goeders1, Craig R Clark, Grahame Vittorini
1Schools of Chemistry and Biochemistry; Computational Science and Engineering; and Physics, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
The Journal of Physical Chemistry. A
|April 9, 2013
Summary
This study non-destructively measures molecular ion masses by co-trapping them with laser-cooled calcium ions. The method uses normal-mode frequencies derived from resolved sideband measurements for precise mass determination.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Information Science
- Spectroscopy
Background:
- Precise mass measurements of molecular ions are crucial for fundamental physics and chemistry.
- Existing methods can be destructive or lack precision.
- Co-trapping with laser-cooled atomic ions offers a promising non-destructive approach.
Purpose of the Study:
- To develop and demonstrate a non-destructive method for measuring the masses of single molecular ions.
- To determine the masses of calcium hydride (CaH+) and calcium oxide (CaO+) molecular ions.
- To investigate the influence of stray electric fields on the measurement technique.
Main Methods:
- Co-trapping a molecular ion with a laser-cooled atomic ion, specifically Calcium-40 (Ca+).
- Measuring normal-mode frequencies of the two-ion system via resolved sideband spectroscopy of a dipole-forbidden transition in Ca+.
- Utilizing different Calcium isotopes to assess stray electric field effects.
Main Results:
- Successfully measured the masses of CaH+ and Ca(16)O+ molecular ions with high precision.
- Demonstrated the feasibility of non-destructive mass determination using co-trapping and resolved sideband spectroscopy.
- Quantified the impact of stray electric fields on the normal-mode frequency measurements.
Conclusions:
- Co-trapping with laser-cooled atomic ions provides a robust method for non-destructive molecular ion mass spectrometry.
- Resolved sideband spectroscopy is a powerful tool for determining normal-mode frequencies and subsequently ion masses.
- The technique shows potential for future applications in molecular spectroscopy and quantum metrology.
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