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Ramsey interferometry is widely used in quantum sensing for precise qubit frequency measurements, but its sensitivity is limited by decoherence. Hecht et al. report a new protocol for detecting qubit frequency shifts in a decohering system which has enhanced sensitivity and is applicable to existing technologies.

Impurity spins in silicon can be controlled with microwaves and then read-out electrically, offering a promising platform for quantum information applications. Here, the authors show that terahertz pulses can be used to address the orbital degree of freedom as well, which can also be detected electrically.

Ionizing radiation can cause simultaneous charge noise in multi-qubit superconducting devices. Here, the authors measure space- and time-correlated charge jumps in a four-qubit system in a low-radiation underground facility, achieving operation with minimal correlated events over 22 h at qubit separations beyond 3 mm.

Coherence between rotational states of polar molecules has previously been limited by light shifts in optical traps. A magic-wavelength trap is able to maximize the coherence time and enables the observation of tunable dipolar interactions.

Decoherence is anathema to quantum systems, as it reduces their performance and stability. Shulman et al.show that real-time Hamiltonian parameter estimation can significantly increase the coherence time of a qubit by enabling continuous adjustment of its control parameters.

The hyperfine states of ultracold polar molecules are a strong candidate for storing quantum information. Identifying and eliminating all detectable causes of decoherence has extended the qubit coherence time beyond 5.6 s in RbCs molecules.

Two-dimensional arrays of trapped ion qubits are attractive platforms for quantum information processing, but rapid reloading remains a challenge. Here the authors use a continuous flux of pre-cooled neutral atoms to achieve fast loading of single ions without affecting the coherence of adjacent qubits.

A tweezer clock containing about 150 ⁸⁸Sr atoms achieves trapping and optical excited-state lifetimes exceeding 40 seconds, and shows relative fractional frequency stability similar to that of leading atomic clocks.

Conveyor-mode spin shuttling using a two-tone travelling-wave potential demonstrates an order of magnitude better spin coherence than bucket-brigade shuttling, achieving spin shuttling over 10 μm in under 200 ns with 99.5% fidelity in an isotopically purified Si/SiGe heterostructure.

Hole spin qubits in germanium have seen significant advancements, though improving control and noise resilience remains a key challenge. Here, the authors realize a dressed singlet-triplet qubit in germanium, achieving frequency-modulated high-fidelity control and a tenfold increase in coherence time.

A quantum computer requires quantum systems that are well-isolated from external perturbations, but which can still be easily manipulated with external fields. A scheme that uses spatially inhomogeneous fields to selectively address neutral-atom qubits while they are in field-insensitive superposition states satisfies these competing needs.

An 11-qubit atom processor comprising two precision-placed nuclear spin registers of phosphorus in silicon is shown to achieve state-of-the-art Bell-state fidelities of up to 99.5%.

Dual-rail encodings of quantum information can be used to detect loss errors, allowing these errors to be treated as erasures. The measurement of dual-rail states with error detection has now been demonstrated in superconducting cavities.

A family of multi-qubit Rydberg quantum gates is developed and used to generate Schrödinger cat states in an optical clock, allowing improvement in frequency measurement precision by taking advantage of entanglement.

The presence of various noises in the qubit environment is a major limitation on qubit coherence time. Here, the authors demonstrate the use a closed-loop feedback to stabilize frequency noise in a flux-tunable superconducting qubit and suggest this as a scalable approach applicable to other types of noise.

Solid-state systems are established candidates to study models of many-body physics but have limited control and readout capabilities. Ensembles of defects in diamond may provide a solution for studying dipolar systems.

We present atom interferometry performed in a laboratory-scale Einstein Elevator over several days with high reproducibility. This table-top experiment enables long-term metrological assessments of quantum inertial sensors in microgravity.

Superconducting circuits are promising for quantum computing, but quasiparticle tunnelling across Josephson junctions introduces qubit decoherence. Ristè et al. convert a transmon qubit into its own real-time quasiparticle tunnelling detector and accurately measure induced decoherence in the millisecond range.

Many-body effects in an interacting spin-orbit coupled Fermi gas are studied with the help of clock spectroscopy. The results provide a simple view of how strong collective dynamics arise from local interactions in the presence of spin–orbit coupling.

An elementary quantum network of two entangled atomic clocks is demonstrated; the high fidelity and speed of entanglement generation show that entangled clocks can offer practical enhancement for metrology.

Interspecies comparisons between atomic optical clocks are important for several technological applications. A recently proposed spectroscopy technique extends the interrogation times of clocks, leading to highly stable comparison between species.

Using a long-lived quantum-dot spin qubit coupled to a GaAs-based photonic crystal cavity, researchers demonstrate complete quantum control of an electron spin qubit. By cleverly controlling the charge state of the InAs quantum dot using laser pulses, optical initialization, control and readout of an electron spin are achieved.

Quantum sensing based on solid-state spins can be improved with the use of adaptive strategies.

Trapped ion quantum systems based on sympathetic cooling use ions of different species. Here the authors demonstrate exchange cooling using two ions of the same species (⁴⁰Ca⁺) by taking advantage of the exchange of energy when the ions are brought close together.

Silicon is a promising material for realization of quantum processors, particularly as it could be naturally integrated with classical control hardware based on CMOS technology. Here the authors report a silicon qubit device made with an industry-standard fabrication process on a CMOS platform.

Spin squeezing in an optical atomic clock based on arrays of neutral atoms is used to realize measurement performance below the standard quantum limit.

The authors fabricate a fluxonium circuit using a granular aluminium nanoconstriction to replace the conventional superconductor–insulator–superconductor tunnel junction. Their characterization suggests that this approach will be a useful element in the superconducting qubit toolkit.

Noise is a fundamental obstacle to the stability of atomic optical clocks. An experiment now realizes the design of a spin-squeezed clock that improves interrogation times and enables direct comparisons of performance between different clocks.

Superconducting qubits are highly sensitive to magnetic fields, limiting their integration with spin-based quantum systems. Here, the authors demonstrate a superconducting qubit that maintains coherence beyond 1T, revealing spin-1/2 impurities and magnetic freezing of flux noise.

Optical clocks with a record low zero-dead-time instability of 6 × 10^–17 at 1 second are demonstrated in two cold-ytterbium systems. The two systems are interrogated by a shared optical local oscillator to nearly eliminate the Dick effect.

Phase-estimation algorithms applied to single electronic spins in diamond allow weak magnetic fields to be measured with high sensitivity and a large dynamic range.

A possible route to scalability of trapped-ion-based quantum computing platforms is to connect multiple modules where ions can be shuttled across different registers. Here, the authors demonstrate fast and low-loss transfer of trapped ions between two microchip modules.

Oceans provide essential ecosystem services to human society, yet the climate impacts on blue capital have long been ignored. Incorporating the latest works on ocean science and economics, researchers show that accounting for the potential damage would almost double the social cost of carbon estimation.

Quantum communication networks would greatly benefit from the possibility to have solid-state emitters being directly interfaced with telecom fibers, without the need for wavelength conversion. Here, the authors demonstrate coherent control of an InAs/InP quantum dot, as well as entanglement between its electron spin and the frequency of a telecom photon.

Reaching a quantum advantage in metrology usually requires hard-to-prepare two-mode entangled states such as NOON states. Here, instead, the authors demonstrate single-mode phase estimation using Fock states superpositions in a superconducting qubit-oscillator system.

An exhausting characterization of the coherence properties of quantum system becomes challenging with increasing system size. Here the authors demonstrate that phonon autocorrelation functions and quantum discord can be measured with local control, and validate it in a string of 42 trapped ions.

Carbon nanotubes are promising hosts for spin qubits, however existing demonstrations show limited coherence times. Here the authors report quantum states in a carbon-nanotube-based circuit driven solely by cavity photons and exhibiting a coherence time of about 1.3 μs.

Repeated error correction creates a logical qubit encoded in the hybrid state of a superconducting circuit and a bosonic cavity, which is shown to be fully controllable under a universal single-qubit gate set.

Despite recent advances with trappedion-based platforms, achieving quantum networks with link efficiency greater than unity on metropolitan scales is still a challenge. Here, the authors demonstrate a multiplexed quantum network generating heralded entanglement at a rate faster than local decoherence.

NASA’s Cold Atom Lab has operated on the International Space Station since 2018 to study quantum gases and mature quantum technologies in Earth’s orbit. Here, Williams et al., report on a series of pathfinding experiments exploring the first quantum sensor using atom interferometry in space.

Er³⁺ is implanted into CaWO₄, a material with non-polar site symmetry free of background rare earth ions, to realize reduced optical spectral diffusion in nanophotonic devices, representing a step towards making telecom band quantum repeater networks with single ions.

Dissipation of the sensor is a limiting factor in metrology. Here, Pfender et al. suppress this effect employing the nuclear spin of an NV centre for robust intermediate storage of classical NMR information, allowing then to record single-spin NMR spectra with 13 Hz resolution at room temperature.

Superconducting qubits are measured using microwaves, posing constraints on its size and thermal budgets. The electro-optic transceiver presented here can be used to perform optical readout without affecting qubit performance.

Gatemons, or gate-tunable transmons, are superconducting qubits based on hybrid Josephson junctions, which typically use extended quantum conductors as weak links. Here the authors report a gatemon made with a carbon-nanotube-based junction, showing improved coherence time compared to graphene-based devices.

Quantum annealers hold promise of outperforming classical computers in solving hard optimization problems, but one main challenge is understanding the role of noise in quantum annealing. Here, the authors characterize the relevant noise sources in a tunable flux qubit, a building block for quantum annealers, and provide a benchmark for future work on highly-coherent quantum annealers.

Synchrotron light sources have wide range of tunable parameters like frequency, intensity. Here the authors demonstrate quantum control of Rydberg states of helium using delay controlled XUV wavepackets generated from synchrotron radiation.