High-Fidelity Quantum State Control of a Polar Molecular Ion in a Cryogenic Environment
We use a quantum-logic spectroscopy (QLS) protocol to control the quantum state of a CaH^{+} ion in a cryogenic environment in which reduced thermal radiation extends rotational state lifetimes by an order of magnitude over those at room temperature. By repeatedly and adaptively probing the molecule, detecting the outcome of each probe via an atomic ion, and using a Bayesian update scheme to quantify confidence in the molecular state, we demonstrate state preparation and measurement (SPAM) in a single quantum state with infidelity less than 6×10^{-3} and measure Rabi flopping between two states with greater than 99% contrast. The protocol does not require molecule-specific lasers and can be generalized, paving the way for high-fidelity quantum control of many other molecular ions.
Authors
- April Sheffield (ORCID: https://orcid.org/0009-0008-2700-6230)
- C. W. Chou (ORCID: https://orcid.org/0000-0002-1637-5136)
- Julian Schmidt (ORCID: https://orcid.org/0000-0001-7588-3811)
- David R. Leibrandt (ORCID: https://orcid.org/0000-0003-1452-4879)
- Dalton Chaffee (ORCID: https://orcid.org/0009-0004-9871-645X)
- D. Leibfried (ORCID: https://orcid.org/0000-0001-8442-625X)
- Baruch Margulis (ORCID: https://orcid.org/0000-0003-0981-4150)
- April Reisenfeld (ORCID: https://orcid.org/0009-0004-9623-6401)
Institutions
- National Institute of Standards and Technology (US)
- Joint Institute for Laboratory Astrophysics (US)
- University of California, Los Angeles (US)
- University of Colorado Boulder (US)
- University of Colorado System (US)
Publication Details
- Journal
- Physical Review Letters
- Published
- 2025-11-10
- DOI
- https://doi.org/10.1103/7ypf-91jr
- Primary Topic
- Cold Atom Physics and Bose-Einstein Condensates
- Type
- article
- Field-Weighted Citation Impact
- 0.00