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Penning trap mass spectrometry is used to measure the electronic transition energy from a long-lived metastable state to the ground state in highly charged rhenium ions with a precision of 10⁻¹¹.

Coherent quantum transition spectroscopy of the spin of a single antiproton is reported, demonstrating Rabi oscillations of the spin and enabling improved measurement of matter/antimatter symmetry using proton and antiproton magnetic moments.

The successful transport of a trapped proton cloud from the antimatter factory of CERN using a transportable, superconducting, autonomous and open Penning-trap system that can distribute antiprotons into other experiments is reported.

High-precision measurements could disclose fundamental dissimilarities between matter and antimatter, which are found imbalanced in the Universe. Here, the authors measure the magnetic moment of the antiproton with six-fold higher accuracy than before, finding it consistent with that of the proton.

The magnetic moment of the proton is directly measured with unprecedented precision using a double Penning trap.

Measuring the hyperfine structure of a single helium-3 ion in a Penning trap enables direct measurement of the nuclear magnetic moment of helium-3 and provides the high accuracy needed for NMR-based magnetometry.

The masses of the exotic calcium isotopes ⁵³Ca and ⁵⁴Ca measured by a multi-reflection time-of-flight method confirm predictions of calculations including nuclear three-body interactions.

Magnetically confined neutral antihydrogen atoms released in a gravity field were found to fall towards Earth like ordinary matter, in accordance with Einstein’s general theory of relativity.

A single-cell-based approach allows the daughters of a damaged cell to be separately tracked following single mitotic events. This technique highlights the different ways in which ultraviolet light and reactive oxygen species cause mutagenesis.

The ALPHA Collaboration reports measurements of the hyperfine components of the 1S–2S transition in trapped antihydrogen. They interpret the results as a test of the invariance of charge–parity–time-reversal symmetry.

Multiple high-precision measurement campaigns at CERN of the antiproton-to-proton charge-to-mass ratio—to a precision of 16 parts per trillion—in a cryogenic multi-Penning trap offer no evidence of charge–parity–time violation, and set stringent limits on the clock-weak-equivalence principle.

Characterizing the correlations of quantum many-body systems is known to be hard, but there are ways around: for example, a new method for measuring out-of-time correlations demonstrated in a Penning trap quantum simulator with over 100 ions.

Antihydrogen studies are important in testing the fundamental principles of physics but producing antihydrogen in large amounts is challenging. Here the authors demonstrate an efficient and high-precision method for trapping and stacking antihydrogen by using controlled plasma.

Spin-flip resonance data are used to place direct constraints on the interaction of ultralight axion-like particles with antiprotons, improving the sensitivity to the corresponding coupling coefficient by five orders of magnitude.

In this work, stable trapping of a two-dimensional Wigner crystal of above 500 ions is achieved, and the quantum simulation of 300 ions with individual state detection demonstrated.

The difference between the mass of an atom and the sum of its building blocks (the binding energy) is a manifestation of Einstein's famous relation E = mc². Superheavy elements have been observed, but our present knowledge of the binding energy of these nuclides is based only on the detection of their decay products, although they represent the gateway to the predicted 'island of stability'. Here, direct mass measurements of trans-uranium nuclides are reported, providing reliable anchor points en route to the island of stability.

A trapped-ion quantum simulator is used to demonstrate tunable long-range spin-spin couplings in two dimensions, relevant to studies of quantum magnetism at a scale that is intractable for classical computers.

There are many quantum systems that act as high-quality quantum harmonic oscillators, and they can be used to store quantum information using the Gottesman–Kitaev–Preskill code. Entangling gates have now been demonstrated between two of these qubits.

Antihydrogen, the bound state of an antiproton and a positron, has been produced at low energies at CERN since 2002. It is of fundamental interest for testing the standard model of elementary particles and interactions. However, experiments so far have produced antihydrogen that is not confined, precluding detailed study of its structure. Here, trapping of antihydrogen atoms is demonstrated, opening the door to precision measurements on anti atoms.

Scattering resonances are quantum effects occurring in low-temperature molecular collisions. Here the authors observe resonances for the six-atom ND₃-H₂/HD systems in velocity map imaging experiments explained by high-level theoretical predictions.

Positrons are key to the production of cold antihydrogen. Here the authors report the sympathetic cooling of positrons by interacting them with laser-cooled Be⁺ ions resulting in a three-fold reduction of the temperature of positrons for antihydrogen synthesis.

A single electromagnetically trapped proton is sympathetically cooled to below ambient temperature by coupling it through a superconducting LC circuit to a laser-cooled cloud of Be⁺ ions stored in a spatially separated trap.

A highly precise measurement of an optical transition in the helium atom has been obtained using state-of-the-art techniques. The result provides a stringent test of QED theory at low energy levels with tools of atomic physics.

The hyperfine splitting of antihydrogen has been measured and is consistent with expectations for atomic hydrogen.

Podocyturia in patients with pre-eclampsia has been widely documented, but the underlying pathology is unknown. A new study highlights the glomerular histological alterations in a unique Dutch cohort of deceased patients with pre-eclampsia. The results suggest an important, albeit controversial, role of parietal epithelial cells in this context.

The precision of laser spectroscopy of highly charged ions is improved by eight orders of magnitude by cooling trapped, highly charged ions and using quantum logic spectroscopy, thereby enabling tests of fundamental physics.

Accurate mass measurements of the indium isotopes adjacent to the doubly magic ¹⁰⁰Sn provide critical benchmarks for ab initio theory, which withstands the challenge.

Contradictory values for the masses of atomic nuclei have cast doubt on the reliability of these widely used quantities. A new mass measurement of the deuteron, the second-simplest atomic nucleus, clarifies the situation.

The CPT theorem (the assumption that physical laws are invariant under simultaneous charge conjugation, parity transformation and time reversal) is central to the standard model of particle physics; here the charge-to-mass ratio of the antiproton is compared to that of the proton, with a precision of 69 parts per trillion, and the result supports the CPT theorem at the atto-electronvolt scale.

Steric effects in a fundamental energy-transfer reaction at collision energies from over 1,000 K down to 20 mK have now been studied. At high energies a pronounced dependence of the reactivity on the reactant orientation is observed, but this effect is not present at the lowest energies because of dynamic reorientation.

Antihydrogen has been created, trapped and stored for 1,000 s. The improved holding time means that we now have access to the ground state of antimatter—long enough to test whether matter and antimatter obey the same physical laws.

In its second measurement campaign, the Karlsruhe Tritium Neutrino experiment achieved a sub-electronvolt sensitivity on the effective electron anti-neutrino mass.

A high-precision, high-field test of quantum electrodynamics measuring the bound-electron g factor in hydrogen-like tin is described, which—together with state-of-the-art theory calculations—yields a stringent test in the strong-field regime.

The magnetic moment of the antiproton is measured at the parts-per-billion level, improving on previous measurements by a factor of about 350.

A very precise measurement of the magnetic moment of a single electron bound to a carbon nucleus, combined with a state-of-the-art calculation in the framework of bound-state quantum electrodynamics, gives a new value of the atomic mass of the electron that is more precise than the currently accepted one by a factor of 13.

The successful laser cooling of trapped antihydrogen, the antimatter atom formed by an antiproton and a positron (anti-electron), is reported.

Crystals of trapped atomic ions can act as nanoscale mechanical oscillators and make ultrasensitive measurements of force and displacement.

These authors demonstrate resonant quantum transitions in a pure antimatter atom—antihydrogen—by using microwave radiation to flip the spin of the positron of an anti-atom in a magnetic trap, thus ejecting the anti-atom.

Quantum gates in 2D ion crystals are more challenging than in 1D. Here, the authors use their 2D ion trap platform and acousto-optical deflectors to demonstrate a 2-qubit gate that can stand the ion micromotion in such configuration.

Microcantilevers made from flexible materials exhibit nonlinear dynamic behaviour such as bistability. Venstra et al.describe how noise induces transitions between the states in a strongly nonlinear vibrating cantilever and exploit the noisy environment to improve the signal transduction.

The scrambling of quantum information in a many-body system leads to the emergence of statistical mechanics and chaotic behaviour. Here the authors establish quantitative relationships between experimentally-measureable correlators, the Rényi entropy and Lyapunov exponents in the Dicke model.

A protein has been engineered so that 24 identical copies self-assemble into a cube-shaped hollow cage 23 nm in diameter and containing a 130-Å-diameter inner cavity. This represents the largest and most porous structure of its type so far.