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Most of the current protocols for learning properties of quantum states are based on the assumption that the states are prepared in the same way over time. Here, the authors show a way to remove this assumption, while incurring only a polynomial increase in sample complexity.

An efficient method has been proposed through which the properties of a complex, large-scale quantum system can be predicted without fully characterizing the quantum state.

Recent work proposed a machine learning algorithm for predicting ground state properties of quantum many-body systems that outperforms any non-learning classical algorithm but requires extensive training data. Lewis et al. present an improved algorithm with exponentially reduced training data requirements.

Randomized measurements provide a feasible procedure for probing properties of many-body quantum states realized in today’s quantum simulators and quantum computers. This Review covers implementation, classical post-processing and theoretical performance guarantees of randomized measurement protocols, surveying their many applications and discussing current challenges.

Excitonics provides a promising way to manipulate light-matter interactions for advanced optical applications, yet controlling core-exciton dynamics in the X-ray regime is challenging. Here, the authors combine experiments with an ab initio approach developed specifically for modelling pump-probe excitations, revealing how photoexcited carrier distributions can be used to control core-exciton resonances at absorption edges.

Functional roles of the parvicellular part of the ventral posteromedial nucleus/gustatory thalamus are not fully understood. Here authors found that gustatory thalamus mediates aversive behaviors and responds to noxious stimuli and fear memory. Gustatory thalamus receives input from the parabrachial nucleus and innervates neurons in the insular cortex and rostral lateral amygdala.

A study demonstrating increasing error suppression with larger surface code logical qubits, implemented on a superconducting quantum processor.

Promethium remains the least studied element among the lanthanide series because of its scarcity and radiolytic nature. Here, the authors report two new isostructural 2,2’:6’,2”-terpyridine compounds of ¹⁴⁷Pm and ²⁴⁸Cm.

Experimental demonstration of quantum speedup that scales with the system size is the goal of near-term quantum computing. Here, the authors demonstrate such scaling advantage for a D-Wave quantum annealer over analogous classical algorithms in simulations of frustrated quantum magnets.

A successful silicon spin qubit design should be rapidly scalable by benefiting from industrial transistor technology. This investigation of exchange interactions between two FinFET qubits provides a guide to implementing two-qubit gates for hole spins.

Collisions between two individual electrons in a quantum nanoelectronic circuit revealed a mutual interaction fully mediated by Coulomb repulsion—an essential building block for two-qubit logic implementations with flying electrons.

The study of excited triplet states in molecular systems is in some cases hindered by the difficulty in accessing them and the intense signals of singlet states. Here, the authors show that the combination of polarized light and molecular alignment can enhance the triplet absorption for sulphur dioxide.

By converting Li-ion battery into an optical device using graphene electrodes, an electrochemical optical device which enables colour changing ability over the entire wavelength range from visible to microwave is demonstrated.

In this study the authors consider the structural variants (SVs) present within cancer cases of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium. They report hundreds of genes, including known cancer-associated genes for which the nearby presence of a SV breakpoint is associated with altered expression.

The authors summarize the data produced by phase III of the Encyclopedia of DNA Elements (ENCODE) project, a resource for better understanding of the human and mouse genomes.

Arrays of nanoparticles grouped into microscale arrays support multiple nanolasing modes that can be tailored by changing the geometry of the superlattice.

A three-photon entangled Greenberger–Horne–Zeilinger state is directly produced by cascading two entangled down-conversion processes. Experimentally, 11.1 triplets per minute are detected on average. The three-photon entangled state is used for state tomography and as a test of local realism by violating the Mermin and Svetlichny inequalities.

Tuning interspecies interactions in atomic Bose–Fermi mixtures is shown to drive the system through a quantum phase transition. This enables the generation of heteronuclear molecules in the quantum-degenerate regime.

Perfect State Transfer is known to time-optimally connect distant nodes in a network. Here, the authors implement it on a chain of superconducting qubits and demonstrate that it also serves as a powerful tool for generating multi-qubit entanglement.

Understanding deregulation of biological pathways in cancer can provide insight into disease etiology and potential therapies. Here, as part of the PanCancer Analysis of Whole Genomes (PCAWG) consortium, the authors present pathway and network analysis of 2583 whole cancer genomes from 27 tumour types.

Analysis of cancer genome sequencing data has enabled the discovery of driver mutations. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium the authors present DriverPower, a software package that identifies coding and non-coding driver mutations within cancer whole genomes via consideration of mutational burden and functional impact evidence.

Carrier multiplication generates multiple excitons for each absorbed photon but is normally limited by fast phonon-assisted relaxation. Here the authors achieve a threefold enhancement in multiexciton yields in Mn-doped PbSe/CdSe quantum dots, due to very fast spin-exchange interactions between Mn ions and the quantum dots that outpace energy losses arising from phonon emission.

Multi-omics datasets pose major challenges to data interpretation and hypothesis generation owing to their high-dimensional molecular profiles. Here, the authors develop ActivePathways method, which uses data fusion techniques for integrative pathway analysis of multi-omics data and candidate gene discovery.

Resonant driving of a nanoscale quantum system coupled to a microscopic mechanical resonator may have uses in precision sensing and quantum information. The authors realize this by tailoring the geometry of a semiconductor nanowire embedding a quantum dot, detecting sub-picometre displacements.

Driven-dissipative microcavity polariton experiments find superfluid-like behaviour but the intuition developed from equilibrium systems cannot be straightforwardly applied. Juggins et al. show coherently-driven polaritons are not superfluid and earlier observations instead arise from a distinct rigid state.

Richard Trembath and colleagues show that mutations in NOTCH2 cause Hajdu-Cheney syndrome, a multisystem disorder marked by severe and progressive bone loss. The mutations are predicted to result in elevated NOTCH2 signaling.

Precisely calculating differences between muon- and electron-neutrino interactions is difficult, but is vital for correctly interpreting neutrino oscillation experiments. Here, the authors determine the effect of electromagnetic quantum corrections in the predicted ratio of v_e and v_μ cross sections.

The magnetic phases of the geometrically frustrated triangular lattice Hubbard model are directly investigated using ultracold fermionic atoms, indicating a possible transition to ferromagnetism at a filling of 1.2.

This overview of the ENCODE project outlines the data accumulated so far, revealing that 80% of the human genome now has at least one biochemical function assigned to it; the newly identified functional elements should aid the interpretation of results of genome-wide association studies, as many correspond to sites of association with human disease.

Hybrid quantum optomechanical systems interface a single two-level system with a macroscopic mechanical degree of freedom. In a microwire with a single embedded semiconductor quantum dot, not only can the wire vibration modulate the excitonic transition energy, but the optical drive of the quantum dot can also induce motion in the wire.

Atmospheric aerosol particles can significantly influence the climate system. Analyses of observations and observation-based modelling data reveal that biogenic aerosol emissions soar in response to warming, exerting a cooling effect in a negative feedback loop.

Fin-shaped transistors can host hole spin qubits at high enough temperatures to potentially enable the scaling and development of quantum computing systems controlled by conventional electronics co-integrated in the same package.

An organic molecule, 5Cz-TRZ, with multiple donor units supports fast reverse intersystem crossing, allowing fabrication of high-performance organic light-emitting diodes.

Recent theory has shown that the non-equilibrium response of a Kondo model can be described by the Fermi liquid theory with three-body correlations. Here, the authors experimentally measure such correlations in the nonlinear conductance of a Kondo-correlated quantum dot.

Rabi dynamics between the ground state and an excited state in helium atoms are generated using femtosecond extreme-ultraviolet pulses from a seeded free-electron laser, which may allow ultrafast manipulation of coherent processes at short wavelengths.

Integrated photonics allows integration of complex optical circuits on a single chip. Here, the authors propose a wavelength division multiplexing based electronic-photonic arithmetic logic unit for computing at high speeds and with improved power consumption to help with the physical limits of Moore’s law.

Using a quantum annealing processor to study three-dimensional spin glasses demonstrates an accurate large-scale quantum simulation of critical dynamics and a scaling advantage over analogous classical methods for energy optimization.

A large-scale programmable quantum simulation is described, using a D-Wave quantum processor to simulate a two-dimensional magnetic lattice in the vicinity of a topological phase transition.

The established means of bandgap control in semiconductors are based on chemical, electrical or optical doping. Here, the authors report wide bandgap modulations in monolayer WS2 at room temperature by coupling the 2D semiconductor to a self-assembled plasmonic crystal inducing coherent hot electron doping.

Breathing is controlled automatically but is also conditionally integrated with behavior and emotion in awake animals. Here, authors identify brainstem neurons that are important for controlling awake-state-dependent breathing patterns in mice.