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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.

Coherent manipulation of hole-orbital states in semiconductor quantum dots is achieved through stimulated Auger processes, opening doors to new types of orbital-based solid-state quantum photonic devices.

High-dimensional quantum bits advance the application of quantum sensing and information processing technologies but suffer from the low spectral selectivity and working temperature. Here the authors present the selective excitation and control of spin qudits modes based on an ensemble of silicon vacancy defects in silicon carbide at room temperature.

A method is described for the generation of large-scale entanglement that can be used for quantum-enhanced sensing even when systems are limited to short-range interactions in experiments with up to 51 trapped ions.

While a quantum system is always disturbed by any observation, one can exploit the back action of measurements and strong couplings to tailor the system evolution via quantum Zeno dynamics. Schäfer et al. demonstrate quantum Zeno dynamics in a five-level Hilbert space using a ⁸⁷Rb Bose–Einstein condensate.

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.

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.

Rydberg molecules—which involve atoms in highly excited electronic states and can be as large as 100 nanometres—have been created recently in cold gases of rubidium atoms. New work demonstrates that the inter-atomic interactions in these long-range molecules can be manipulated coherently, enabling controlled ‘making and breaking’ of the bond using laser light.

The coherence time during which two energetic states in a semiconductor are synchronized can be very short. Here, the authors demonstrate that despite their brief coherence times, coherent control of such states can be achieved 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.

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.

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.

High sensitivity in quantum sensing comes often at the expense of other figures of merit, usually resulting in distortion. Here, the authors propose a protocol with good sensitivity, readout linearity and high frequency resolution, and benchmark it through signal measurements at audio bands with NV centers.

A single excitation in a semiconductor nuclear spin ensemble is detected with parts-per-million accuracy using the coupling between the ensemble and an electron-spin quantum dot.

Open quantum systems are subject to dephasing that ultimately destroys the information they hold. Here, the authors use a superconducting qubit to show that dephasing also has a geometric origin, which can either reduce or restore coherence depending on the path of the quantum system in its Hilbert space.

Using a cryogenic 300-mm wafer prober, a new approach for the testing of hundreds of industry-manufactured spin qubit devices at 1.6 K provides high-volume data on performance, allowing optimization of the complementary metal–oxide–semiconductor (CMOS)-compatible fabrication process.

Quantum coherent control of single-photon-emitting defect spins have been reported in hexagonal boron nitride, revealing that spin coherence is mainly governed by coupling to a few proximal nuclei and can be prolonged by decoupling protocols.

The experimental demonstration of many-body signal amplification in a solid-state, room-temperature quantum sensor is reported.

This study quantifies the social costs of aviation’s CO₂ emissions and contrail cirrus. Targeting flights with high contrail cirrus impacts could substantially reduce aviation’s climate damages.

In a step towards developing a system in which to study quantum magnetism, the long-range dipolar interactions of polar molecules pinned in a three-dimensional optical lattice are used to realize a lattice spin model.

The authors find a correspondence between dynamic ratings of subjective experience and brain network dynamics during a naturalistic auditory story. They then explore which networks differentially support individual-specific and shared experiences.

Economists often dominate public climate policy discussions, such as those on the proper social discount rate and optimal climate pathways. This Article shows that philosophers, experts in underlying ethical matters, generally agree with economists but put more weight on various normative considerations.

The coherent operation of individual ³¹P electron and nuclear spin qubits in a ²⁸Si substrate shows new benchmark decoherence times and provides essential information on the dechorence mechanism.

D. Iyama et al. study the generation and quantum coherence of Schrödinger cat states in a superconducting Kerr parametric oscillator, a Kerr nonlinear resonator with a two-photon pump. They also manipulate the quantum interference of the cat states by implementing single cat-state gate operations.

Operation sweet spots decouple hole spin qubits in silicon from charge noise while conserving full electrical control and allowing for spin coherence times of up to 88 μs.

A microwave signal can be used to control semiconductor charge qubits with high fidelity.

High-fidelity control and readout of a superconducting qubit is performed with a low-noise optical fibre link that delivers microwave signals directly to the millikelvin quantum computing environment.

Silicon-based spin qubits are promising candidates for a scalable quantum computer. Here the authors demonstrate the violation of Bell’s inequality in gate-defined quantum dots in silicon, marking a significant advancement that showcases the maturity of this platform.

An electronic analogue of a Michelson–Morley experiment, in which an electron wave packet bound inside a calcium ion is split into two parts and subsequently recombined, demonstrates that the relative change in orientation of the two parts that results from the Earth’s rotation reveals no anisotropy in the electron dispersion; this verification of Lorentz symmetry improves on the precision of previous tests by a factor of 100.

An individual electron is used as a quantum sensor to realize atomic-scale magnetic resonance imaging.

A scalable silicon quantum processor unit cell made of two qubits confined to quantum dots operates at about 1.5 K, achieving 98.6% single-qubit gate fidelities and a 2 μs coherence time.

Qubits in solid state systems like point defects in diamond can be influenced by local strain. Here the authors use surface acoustic waves to coherently control silicon vacancies in diamond, which have the potential to reach the strong coupling regime necessary for many applications.

Quantum simulators offer a test bed to emulate physical phenomena that are difficult to reproduce numerically. Using a multi-element superconducting quantum circuit, Chen et al.emulate weak localization for a mesoscopic system using a control sequence that lets them continuously tune the level of disorder.

Qudits, higher-dimensional analogues of qubits, expand quantum state space for information processing using fewer physical units. Here the authors demonstrate control over a 16-dimensional Hilbert space, equivalent to four qubits, using combined electron-nuclear states of a single Sb donor atom in Si.

While most results so far in semiconductor spin-based quantum computation use electron spins, devices based on hole spins may have more favourable properties for quantum applications. Here, the authors demonstrate single-shot readout and coherent control of a qubit made from a single hole spin.

A programmable neutral-atom quantum computer based on a two-dimensional array of qubits led to the creation of 2–6-qubit Greenberger–Horne–Zeilinger states and showed the ability to execute quantum phase estimation and optimization algorithms.

Quantum computing requires fast and selective control of a large number of individual qubits while maintaining coherence, which is hard to achieve concomitantly. All-electrical operation of a hole spin qubit in a Ge/Si nanowire demonstrates the principle of switching from a mode of selective and fast control to idling with increased coherence.

Exotic theories predict the violation of Lorentz symmetry, which could potentially be spotted in low-energy experiments. Using ytterbium ions could improve the current sensitivity bounds by five orders of magnitude.

Gas-phase actinium monofluoride (AcF) has been produced and spectroscopically studied at the CERN-ISOLDE radioactive ion beam facility; the results highlight the potential of ²²⁷AcF for exceptionally sensitive searches of CP violation.

Motion of electrons can influence their spins through a fundamental effect called the spin–orbit interaction. Here, a spin–orbit quantum bit (qubit) is implemented in an indium arsenide nanowire, which should offer significant advantages for quantum computing. The spin–orbit qubit is electrically controllable, and information can be stored in the spin. Moreover, nanowires can serve as one dimensional templates for scalable qubit registers, and are suited for both electronic and optical devices.

Silicon carbide is a polymorphic material with over 250 known crystal structures. Here the authors show that such polymorphism can be used as a degree of freedom for engineering optically addressable and coherently interacting spin states, including many with room-temperature quantum coherence.

Researchers demonstrate coherent control of an exciton qubit in a semiconductor quantum dot through optoelectronic means. Such state manipulation of single quantum systems is essential for the development of quantum information systems.

Free-electron Ramsey imaging enables space-, time- and phase-resolved electron imaging of weak optical near fields. Owing to its phase-resolving ability, this technique images chiral vortex–anti-vortex phase singularities of phonon-polariton modes in hexagonal boron nitride.

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