Walz works on precision spectroscopy of exotic atoms and antimatter. The group is known for continuous-wave Lyman-alpha (121.6 nm) laser sources -- the enabling technology for laser cooling of antihydrogen -- and for antihydrogen and positronium spectroscopy aimed at CPT tests and at antimatter gravity measurements, in collaboration with CERN antiproton-decelerator experiments. Complementary work at Mainz covers laser development, exotic-atom trapping and detection. Relative to the established NV-ensemble quantum-sensing playbook (DEER, nanoscale NMR, T1 relaxometry at pT/sqrt(Hz) ensemble sensitivity), this is a fundamental-symmetry pivot: the sensing content is in ultra-stable lasers, extreme-vacuum trapping and single-particle detection rather than solid-state spins, and it suits a postdoc looking to move from quantum sensors toward fundamental-physics tests.
The LARISSA group develops multi-step resonance ionization laser spectroscopy and RIMS: element- and isotope-selective laser ionization used both as an ultratrace analytical technique (actinide detection at extreme selectivity, environmental and nuclear-forensic samples) and as a spectroscopy tool for exotic and short-lived isotopes, feeding ion-source development for facilities such as ISOLDE/CERN. A major current thrust is the atomic and ionic spectroscopy of thorium, including the 229mTh isomer that underpins the nuclear-clock effort, done jointly with Schmidt-Kaler's trap group and Duellmann's nuclear chemistry. Relative to the established NV-ensemble quantum-sensing playbook (DEER, nanoscale NMR, T1 relaxometry at pT/sqrt(Hz) ensemble sensitivity), the transferable capability here is selective, quantum-state-resolved detection of single atoms/ions -- the readout problem, approached spectroscopically rather than magnetically.
Wolf works on trapped-ion quantum sensing, using the motional degrees of freedom of single ions and small crystals as transducers for weak electric fields and forces, together with non-classical motional states (squeezed and Fock states) to enhance the achievable sensitivity. The broader agenda is to use trapped ions as a testbed for fundamental measurement limits — quantum-enhanced amplification of small displacements, quantum non-demolition readout of motion — with an eye to applications in electric-field metrology and searches for new physics. Positioned against the established body of NV-ensemble quantum sensing work — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — trapped-ion motional sensing is the cleanest available platform for demonstrating the entanglement-enhanced scaling that NV ensembles at pT/sqrt(Hz) approach only in the shot-noise-limited regime. Early-career independent PI within the Quantum Control Laboratory; smaller group, higher autonomy.