Technique - (9) Mass spectrometry / ion trap

Type: Experimental

Description: Precision mass measurement of ions using Penning or Paul traps.

Department(s)/lab(s): Physics – Institute for Quantum Electronics | Quantum Control for Fundamental Physics Group (Craik Group) @ ETH Zurich
Summary:

Craik leads the RAVIOLIS project (SNSF Starting Grant, started July 2025) measuring atomic parity violation in barium ions at <0.1% precision. Her entanglement protocol uses multi-ion entangled states with photonic integrated waveguide addressing to common-mode-reject parity-conserving systematics. Previous work: precision measurement of Ba+ dipole transition probabilities below 1% uncertainty; first laser-guided individual addressing of Ba+ qubits with <10^-4 intensity crosstalk; isotope-shift spectroscopy in Ca+ for fifth-force searches. She is actively recruiting for postdocs and PhD students for the new Ba+ ion trap experiment.

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 – Institute for Quantum Electronics | Trapped Ion Quantum Information Group (Home Group) @ ETH Zurich
Summary:

Home leads the TIQI group working with Be+ and Ca+ trapped ions. Research directions: (1) Quantum error correction β€” fault-tolerant gates, surface code implementations with multi-ion chains; (2) Precision metrology β€” ytterbium ion optical clock, mixed-species ion chain spectroscopy and ytterbium HFS measurements; (3) Macroscopic superposition and quantum contextuality β€” creating nonclassical motional states in harmonic oscillators for tests of quantum foundations; (4) Scalable architectures β€” photonic integrated waveguides for individual ion addressing, quantum logic detection of spectroscopy ions. Key publications include first two-qubit gates with mixed species and records in quantum state readout fidelity. Lab is investigating quantum logic-enhanced spectroscopy of complex atomic systems.

Department(s)/lab(s): Chemistry / Pharmacy | Li Lab (Mass Spectrometry & Molecular Imaging) @ UWMadison
Summary:

Develops mass spectrometry-based imaging and proteomics technologies, including integration of tissue expansion microscopy with mass spectrometry imaging to achieve higher spatial resolution molecular maps of tissues such as tumors and brain.

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 & Astronomy | Schuessler Laser Spectroscopy & Ion Trap Group @ TAMU
Summary:

Schuessler combines optical frequency combs with cavity-enhanced and mid-IR spectroscopy for ultrasensitive trace-gas and isotopic detection, and runs ion-trap precision mass/laser spectroscopy of exotic species. In the broader landscape of NV-centre ensemble quantum sensing (DEER, nano-NMR, T1 relaxometry) operating near pT/sqrt(Hz) sensitivity, this work is a comb-metrology counterpart to spin-based chemical sensing.

Department(s)/lab(s): Chemistry | Sweedler Lab @ UIUC
Summary:

Develops single-cell and mass-spectrometry imaging technologies to discover and map neuropeptides and other small-molecule signaling agents involved in cell-cell communication.

Department(s)/lab(s): Chemistry | Zare Lab @ Stanford
Summary:

Zare's group develops laser and mass-spectrometric methods -- including single-cell mass spectrometry and mass spectrometry imaging of neuropeptides -- to chemically profile individual cells and tissue sections with high molecular specificity, alongside long-standing work in microdroplet and chiral-selective chemistry.