An order-of-magnitude improvement in time-delay measurements is achieved by devising a method inspired by multiparameter estimation.

An on-chip entangled-photon pair source from an AlGaAs-on-insulator microring resonator is demonstrated, offering a nearly 1000-fold improvement over state-of-the-art brightness while maintaining >97% fidelity and >99% purity.

Important challenges for successfully adopting indium arsenide quantum dots as a platform for quantum devices are solved, bringing in new competitive advantages to the realm of semiconductor technologies.

A journey through several theoretical approaches to measurement-induced phase transitions is presented: exact results are shown to be possible in some cases, and new lines of inquiry are opened up, with outstanding questions clearly delineated.

Perspective: A unified view reveals connections between quantum optimal control and variational quantum algorithms, bringing forward ways of advancing both fields.

Three proposals to implement quantum verification in the near-term are outlined, bringing together knowledge from experimentalists, theorists, and computer scientists.

A back-of-the-envelope analysis shows the conditions for current quantum error-correcting codes and architectures to outperform classical computers.

Prominent protocols that allow certifying the proper functioning of quantum devices are thoroughly discussed, providing a high-level guide for newcomers.

An order-of-magnitude improvement in time-delay measurements is achieved by devising a method inspired by multiparameter estimation.

A high gain, high power handling, broadband amplifier with simultaneous near-quantum-limited performance is demonstrated.

The conditions to use parity readout, a qubit measurement method applicable in large-scale silicon quantum computing, are established.

Network theory is used to predict satellite-based quantum communications as the preferred form for achieving efficient information transfers.

High-resolution sensing of weak signals is implemented by means of an integrated diamond—nuclear-magnetic-resonance technique

A thermodynamic description on quantum scrambling for open quantum system dynamics is formulated, leading to universal applications that range from black holes to ion trap systems.

Experimental implementation of “shadow tomography”: Using a limited number of measurements, the method is demonstrated to outperform conventional state reconstruction of a system’s property, such as fidelity.

An analytical procedure to certify secret randomness, occurring when measurement outcomes are non-locally correlated, is developed for networks consisting of three or more parties.

The reason why quantum approximate optimization algorithms work to prepare some quantum states but not others is addressed, shining light into its capabilities and limitations.

A hybrid network structure of superconductors and quantum dots is theoretically shown to represent a rich platform for exploring nontrivial non-Abelian 4D topology.

The dynamics of solid-state qubits coupled to a bath of nuclear spins at avoided crossings are investigated theoretically and experimentally, uncovering the nature of the decoherence process at clock transition.

Rare-earth ions with nuclear spins in an insulating crystal constitute a promising quantum computing platform, with rapidly configurable two-qubit gates enabled by long-range magnetic dipolar interactions.

An axiomatic approach to channel divergences, particularly dynamical relative entropies, based on an extension of the data processing inequality, is presented.

A recipe to simulate chemistry at the single-molecule level in a trapped-ion platform is presented, enabling a high-precision investigation in previously unattainable regimes.

The prospects of quantum advantage using NISQ devices to solve linear algebra problems are shown to be fairly small.

A neural network is constructed to learn the environment of an arbitrary qubit, allowing the underlying noise spectrum to be extracted in a manner that is more accurate and experimentally efficient than existing methods.

Simulations of the finite-temperature quantum dynamics of spin systems are performed on digital quantum computers, enhancing many capabilities that are critical to study realistic many-body physics on near-term quantum hardware.

An explicit scheme for the optimal approximation of a quantum state using a finite but incomplete set of observables is outlined.

The problem of modeling large driven dissipative quantum systems is tackled with a phase space method, opening the way to progress on a myriad of experimental platforms described by a Bose Hubbard model, including highly non-uniform systems with tens of thousands of sites.

Playing with causal orders leads to quadratic speed-up: An efficient algorithm is introduced and implemented in a scalable fiber-optic based experiment that achieves, for the first time, a quantum 4-switch gate.

Important challenges for successfully adopting indium arsenide quantum dots as a platform for quantum devices are solved, bringing in new competitive advantages to the realm of semiconductor technologies.

An accurate and efficient way to estimate the noise on a quantum computer is devised, enabling the recovery of noise rates as small as 1 part in 10,000.

Error reduction of several orders of magnitude in a quantum simulation may be possible by using a technique that explores symmetry protection.

The impact of hardware noise on quantum circuits is circumvented using a machine learning strategy that outputs the best circuit design for optimizing the performance of a given algorithmic task under the noisy environment.

A new signature of quantum gravity, connected to a concept used in the area of quantum computation, may enable a table-top test of quantum gravity using just a single quantum system and without assumptions on locality.

An investigation of group covariant quantum error correction indicates that the Eastin-Knill theorem, a stumbling block on the path to fault-tolerant quantum computation, may be circumvented by using continuous variables.

Cubic phase states, sought as a resource for universal computation, can be experimentally created using the recently produced trisqueezed states and simple Gaussian operations.

Quantum computing and artificial intelligence are better integrated using an approach based on a new class of physics-inspired methods: New quantum algorithms can provide boosts to energy-based deep reinforcement learning.

Using an approach based on the synergy between the techniques of quantum information and many-body physics, a study of quantum circuits indicates that the quality of being classically simulated can coexist with having high complexity.

To better understand the classical-quantum boundary, a geometrical method is developed, establishing what characteristics of a physical theory give rise to (non)contextuality.

A deeper investigation shows how the shapes of an operational theory’s state and effect spaces determine whether the predictions of the theory admit of a classical (noncontextual) explanation.

Quantum state discrimination is made easier: A practical strategy to beat the standard quantum limit at low input power and without adaptive feedback is demonstrated.

A variational-parameter-free method is brought to the quantum realm, providing substantial improvements for the calculation of ground states on quantum computers.

An algorithmic approach to assess the potential of hybrid topological quantum computers is developed, allowing one to remove excess non-topological gates and reduce the impact of noise on the compiled braid circuits.

The security of quantum solutions for an important cryptographic taskbetween mistrustful parties is examined, and a concrete protocol withproven bounds on cheating is experimentally realized.

A framework for deriving tight, and therefore more predictive, bounds on the evolution of quantum devices is presented within the body of quantum thermodynamics.

An on-chip entangled-photon pair source from an AlGaAs-on-insulator microring resonator is demonstrated, offering a nearly 1000-fold improvement over state-of-the-art brightness while maintaining >97% fidelity and >99% purity.

A set of theoretical tools and numerical examples, capturing the current limitations of quantum hardware, is developed to significantly improve the performance of optimization algorithms.

A promising building block for a fault-tolerant quantum processor is demonstrated: Exponential protection against relaxation and first-order protection against dephasing is achieved in a superconducting qubit.

A master equation is derived to describe quantum systems connected to dynamically-evolving mesoscopic baths, progressing towards the control of nanoscale quantum technologies such as engines and refrigerators.

Real-time suppression of errors in quantum logic operations may be achieved by a geometrical technique that allows one to shape noise-canceling pulses.

A quantum-classical hybrid algorithm that is suitable for NISQ devices is developed to efficiently simulate aspects of non-equilibrium dynamics.

A fundamental limit in quantum metrology is obtained: The achievable sensitivity enhancement allowed by quantum strategies is determined, and protocols to reach such levels are proposed.

A universal approximation for the Renyi entropies of equilibrated pure states is presented, helping to understand how the process of thermalization is consistent with unitarity in quantum chaotic systems and models of evaporating black holes.

Classical simulation of quantum circuits is investigated in the context of quantum resource theories, bringing up several fundamental insights and leading to improved simulation algorithms.

The measurement cost of running a variational quantum algorithm can be reduced using a technique based on quantum amplification.

Silicon spin qubit arrays are disrupted by Ge nuclear dynamics.

Qubits in hole silicon fin field-effect transistors can be made charge-noise free by on-demand switching ON and OFF the spin-orbit coupling.

A framework for simulating nonperturbative effects of field theory using a quantum annealer is presented and implemented.

A Bose-Einstein condensate quantum simulator, in experimentally achievable conditions, can be used to investigate aspects of the evolution of the early universe.

Experimentally relevant benchmarking options are proposed, expanding the available choices of benchmarking group while keeping the required resources comparable with previous methods.

A journey through several theoretical approaches to measurement-induced phase transitions is presented: exact results are shown to be possible in some cases, and new lines of inquiry are opened up, with outstanding questions clearly delineated.

Measurement of the electron spin of a quantum dot indicates that CMOS-compatible manufacturing processes are promising for fabricating long-lived silicon qubits.

Roadmap: The dual challenge of building quantum computers and finding their applications is addressed in a holistic way that calls for coordinated community actions.

Roadmap: The integration of diverse physical platforms into functioning quantum networks is discussed, highlighting pathways to accelerate the development of quantum interconnects.

Roadmap: The principles and implementation of quantum simulators are discussed, outlining their near- and long-term prospects to achieve scientific and technological breakthroughs.