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Electron spins generated by phosphorus dopant atoms buried in silicon represent well-isolated quantum bits with long coherence times, but so far the control of such single electrons has been insufficient to use them in this way. These authors report single-shot, time-resolved readout of electron spins in silicon, achieved by coupling the donor atoms to a charge-sensing device called a single-electron transistor. This opens a path to the development of a new generation of quantum computing and spintronic devices in silicon.

A large nuclear spin has been successfully placed in a Schrödinger cat state, a superposition of its two most widely separated spin coherent states. This can be used as an error-correctable qubit.

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.

Donors spins in silicon are coherent, high-performance qubits, but scale-up has been challenging. Here the authors present the first experimental demonstration of exchange-based, entangling two qubit gates between electrons bound to ³¹P donors in Si.

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.

Individual spins, associated with vacancies in the silicon carbide lattice, have been observed and coherently manipulated. This may offer new directions for integrated spintronic devices.

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 the size of silicon transistors in conventional computers shrinks towards the atomic scale, the quantum states of atoms and quantum dots in silicon are being investigated for quantum information processing.

For solid-state qubits, the material environment hosts sources of errors that vary in time and space. This systematic analysis of errors affecting high-fidelity two-qubit gates in silicon can inform the design of large-scale quantum computers.

Operating donor-based quantum computers in silicon is hindered by the dependence of inter-qubit coupling on the precise donor position. Here, the authors show controlled rotation operation on exchange-coupled electron spins in the weak-exchange regime, loosening the requirements on positioning precision.

African Americans have an elevated risk of developing chronic kidney disease, yet only a fraction of those with high-risk genotypes develop the disease. Here, the authors show that a missense variant in APOL1 has a strong protective effect when co-inherited with the high-risk G2 allele of APOL1, with important implications for clinical practice and translational research.

Coherent quantum control of a single ¹²³Sb nucleus using electric fields produced within a silicon nanoelectronic device is demonstrated experimentally, validating a concept predicted theoretically in 1961.

At the quantum limit, vacuum fluctuations determine the precision with which a signal can be measured. In this work the authors use a technique known as squeezing to greatly reduce the vacuum fluctuation noise present at microwave frequencies.

Initialization and operation of spin qubits in silicon above 1 K reach fidelities sufficient for fault-tolerant operations at these temperatures.

A violation of Bell's inequality, which is a direct proof of entanglement, can be observed in the solid state using the electron and nuclear spins of a single phosphorus atom in silicon.

The coherent manipulation of an individual electron spin qubit bound to a single phosphorus donor atom in natural silicon provides an excellent platform on which to build a scalable quantum computer.

Electrical detection and coherent manipulation of a single ³¹P nuclear spin qubit is reported; the high fidelities are promising for fault-tolerant nuclear-spin-based quantum computing using silicon.

Universal quantum logic operations with fidelity exceeding 99%, approaching the threshold of fault tolerance, are realized in a scalable silicon device comprising an electron and two phosphorus nuclei, and a fidelity of 92.5% is obtained for a three-qubit entangled state.

One-dimensional microwave Bragg gratings make it possible to coherently control donor nuclear spins in silicon by purely electrical means.

Quantum computers will require a large network of coherent qubits, connected in a noise-resilient way. Tosi et al. present a design for a quantum processor based on electron-nuclear spins in silicon, with electrical control and coupling schemes that simplify qubit fabrication and operation.

High-performance all-electrical control is a prerequisite for scalable silicon quantum computing. The switchable interaction between spins and orbital motion of electrons in silicon quantum dots now enables the electrical control of a spin qubit with high fidelity and speed, without the need for integrating a micromagnet.

A terbium-based molecular magnet, containing four nuclear quantum states, or a qudit, experimentally validates the Grover algorithm for database searches.

Although quantum physics underpins the behaviour of nanoscale objects, its role in nanoscience has been mostly limited to determining the static, equilibrium properties of small systems. This Review describes seminal developments and new directions for the explicit exploitation of quantum coherence in nanoscale systems, a research area termed quantum-coherent nanoscience.

Instead of using capacitively coupled charge sensors, which imply additional complexity in the device architecture, radiofrequency reflectometry on the gate defining the quantum dot can read out the spin state of a double quantum dot in a single shot.

Nuclear spins are excellent qubits, but long-range interactions are difficult to establish. Here, the authors couple a ²⁹Si nuclear spin to electrons in a lithographically defined quantum dot and show initialization, readout and entanglement with the electron spin. The ²⁹Si retains its coherence under electron transfer between quantum dots.

Semiconductor qubits are expected to have diverse future quantum applications. This Review discusses semiconductor qubit implementations from the perspective of an ecosystem of applications, such as quantum simulation, sensing, computation and communication.

Combined analysis of proton-proton collision data from the Large Hadron Collider at CERN by the CMS and LHCb collaborations leads to the observation of the extremely rare decay of the strange B meson into muons; the result is compatible with the standard model of particle physics, and does not show any signs of new physics, such as supersymmetry.