Technique - (9) Molecular beam / ion trap precision spectroscopy

Type: Experimental

Description: Laser spectroscopy of trapped molecular ions at millikelvin temperatures for fundamental symmetry tests and constant-variation searches.

Department(s)/lab(s): Physics & Astronomy – AMOPP | Molecular Quantum Matter Lab (Caldwell Group) @ UCL
Summary:

Caldwell is a Royal Society University Research Fellow establishing the Molecular Quantum Matter Lab at UCL. Research directions: (1) Precision molecular spectroscopy for dark matter and fifth-force searches β€” measuring isotope shifts in molecular systems to test Standard Model predictions and probe new forces between neutrons and electrons; (2) Quantum control of molecules in external fields β€” laser cooling, Stark deceleration, and magneto-optical trapping of polar molecules; (3) Molecular beam spectroscopy with frequency comb referencing for ultra-high-precision lineshape measurements. The lab aims to build the most precise molecular spectrometer for BSM physics searches. Actively building the lab and seeking motivated students/postdocs.

Department(s)/lab(s): Physics | Doyle Group @ Harvard
Summary:

Doyle's group laser-cools and traps polyatomic and diatomic molecules (including CaF and YbOH) using cryogenic buffer-gas sources, applying them to precision tests of fundamental physics such as the electron electric dipole moment (ACME-style eEDM measurement) and to molecule-based quantum information. This precision-measurement approach to fundamental-symmetry tests is a borderline but included case under the quantum-sensing umbrella, given its shared cold-molecule-platform lineage with atomic/vapor sensing and inertial-sensing work.

Department(s)/lab(s): Physics | Fan Group @ Harvard
Summary:

Fan is a junior faculty member specializing in searches for physics beyond the Standard Model through precision measurements using ion traps and molecules. Included as a borderline quantum-sensing/precision-measurement case, analogous to eEDM-style molecular and ion-trap metrology elsewhere in the department.

Department(s)/lab(s): Physics | Garcia Ruiz Lab (Laboratory for Exotic Molecules and Atoms) @ MIT
Summary:

NON-PREFERRED (borderline precision-measurement pivot, kept for review). Garcia Ruiz develops precision laser spectroscopy of atoms and molecules built from short-lived radioactive nuclei (at CERN-ISOLDE and the new FRIB facility) to measure nuclear charge radii, moments, and to search for symmetry-violating effects (parity/time-reversal violation) analogous to eEDM searches; it is fundamental precision measurement rather than a deployable quantum sensor, but shares techniques and motivation with the eEDM/precision-AMO quantum-sensing cluster.

Department(s)/lab(s): Physics & Astronomy – AMOPP | Hogan Group (Rydberg Atoms and Molecules) @ UCL
Summary:

Hogan's group studies atoms and molecules in high Rydberg states for precision measurements and quantum sensing. Research directions: (1) Rydberg atom electric field sensing β€” Rydberg atoms exhibit enormous electric polarizabilities; Stark-map and EIT-based electrometry with sub-mV/cm sensitivity and GHz-range frequency coverage; (2) Rydberg molecule spectroscopy β€” long-range Rydberg molecules as probes of intermolecular forces; (3) Stark deceleration and trapping of Rydberg atoms/molecules β€” producing cold samples for precision spectroscopy and scattering experiments; (4) Circular Rydberg states β€” extremely long-lived states for quantum information storage and sensing. Collaborates on quantum-enhanced sensing of RF/microwave fields.

Department(s)/lab(s): Physics | Exotic Atom Spectroscopy Group @ Imperial
Summary:

Hori performs precision two-photon laser spectroscopy of antiprotonic helium and other exotic atoms (much of it carried out at CERN's Antiproton Decelerator), testing CPT symmetry and QED and constraining the antiproton-to-electron mass ratio.

Department(s)/lab(s): Department of Chemistry & Applied Biosciences (D-CHAB) – IMPS | Molecular Physics and Spectroscopy Group (Merkt) @ ETH Zurich
Summary:

Merkt leads the Molecular Physics and Spectroscopy group at ETH D-CHAB. Research directions: (1) High-resolution XUV/VUV spectroscopy β€” using synchrotron radiation and table-top laser sources to study molecular Rydberg states, ionization thresholds, and ro-vibrational structure at sub-MHz precision; (2) Precision molecular clock transitions β€” proposing and measuring molecular transitions suitable for fundamental constant variation searches (ΞΌ, Ξ±); (3) Metastable atom and ion trapping β€” developing new trapping methods for precision spectroscopy of exotic species; (4) Pulse and Fourier transform microwave spectroscopy β€” rotational spectroscopy of transient species. Direct applications to molecular quantum sensing and fundamental physics.

Department(s)/lab(s): Physics and Astronomy | Odom Research Group @ Northwestern
Summary:

The Odom Group studies trapped molecular ions at millikelvin temperatures using radio-frequency ion traps. Key directions: (1) Controlled preparation and single-quantum-state readout of trapped molecular ions (e.g., AlH⁺, SiO⁺, N₂⁺) β€” combining laser cooling, blackbody-radiation-assisted state preparation, and fluorescence detection for single-molecule precision spectroscopy; (2) Search for time-variation of fundamental constants (electron-to-proton mass ratio, fine structure constant Ξ±) using molecular vibrational/rotational transitions as highly sensitive probes; (3) Quantum effects in sub-Kelvin chemistry β€” probing tunneling, orbiting resonances, and quantum state control of reactive collisions between cold molecules. Member of CFP Northwestern.

Department(s)/lab(s): Physics (Cavendish Astrophysics) | Cambridge Exoplanet Research Group (Queloz) @ Cambridge
Summary:

Queloz (2019 Nobel Prize, co-discoverer of 51 Peg b) leads exoplanet research at Cambridge, including precision radial velocity spectrograph development and transit photometry. He chairs the CHEOPS space mission science team and is founding director of the Leverhulme Centre for Life in the Universe at Cambridge. Research focuses on characterizing transiting terrestrial planets (especially around M dwarfs including TRAPPIST-1) and atmospheric biosignature detection with JWST-era instruments. Part-time appointment at University of Geneva.