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Faithful transfer of quantum states between different parts of a single complex quantum circuit will become more and more important as quantum computing devices grow in size. Here, the authors transfer single-qubit excitations, two-qubit entangled states, and two excitations across a 6 × 6 superconducting qubit device.

An ultra-low-loss integrated photonic chip fabricated on a customized multilayer silicon nitride 300-mm wafer platform, coupled over fibre with high-efficiency photon number resolving detectors, is used to generate Gottesman–Kitaev–Preskill qubit states.

Brain slices offer an experimental window into human neurophysiology. Using high-density microelectrode array recordings and adeno-associated virus–mediated optogenetics, the authors demonstrate that optogenetic targeting of CAMK2A+ neurons can affect network activity in human hippocampal slices.

The Consistent Histories formalism can solve paradoxes in quantum mechanics, but finding such consistent sets of histories requires a computational overhead which is exponential in the problem’s size. Here, the authors report a variational hybrid algorithm solving this problem using polynomial resources.

Minimization of kinetic energy leads to ferromagnetic correlations between itinerant electrons in MoSe₂/WS₂ moiré lattices even in the absence of exchange interactions.

Monitoring internal loads in the human musculoskeletal system has been challenging, especially during dynamic movement. Here, the authors present a wearable joint torque estimation strategy using A-mode ultrasound and demonstrate its effectiveness during various real-world activities.

Hong et al. show that activation of the medial prefrontal cortex induces REM sleep via its projections to the lateral hypothalamus, thus demonstrating a critical role of the cortex in the regulation of REM sleep.

In their analysis of two datasets, Djonlagic et al. identify 23 objective sleep metrics that predict cognitive performance and processing speed in older adults.

This study uses human astrocytes and glioma tumorspheres to generate an atlas of mutant-IDH1-induced epigenomic reprogramming. The findings have implications for understanding mutant IDH function and for optimizing approaches to target IDH-mutant tumors.

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.

More than 40 years ago Berezinskii, Kosterlitz and Thouless (BKT) predicted a state of matter characterized by topological order driven by the binding of vortex-antivortex pairs. Here Tutsch et al.report experimental evidences of BKT physics in a two-dimensional spin-dimer system.

High frequency oscillations (HFO) are a promising biomarker for identifying epileptogenic zones without the need to monitor spontaneous seizure episodes. Here the authors report that there is much variability in the location of HFOs offering a note of caution toward using HFO locations from short recordings as a guide for surgery.

In order to better distinguish the neural processing of speech versus language, this study measured brain responses to foreign speech that was temporally scrambled to varying extents. Using this manipulation to highlight sensitivity to speech independent of linguistic structure, the authors identify a bilateral locus of speech analysis in the superior temporal sulcus.

Shuman et al. report that epileptic mice harbor desynchronized hippocampal interneuron activity and unstable spatial representations, revealing that precise intrahippocampal synchronization is critical for spatial coding.

Electric fields can be used to manipulate molecular spin qubits, but the mechanisms underlying spin-electric coupling are not well understood. Here, the authors investigate the influence of hyperfine coupling between electron and nuclear spins on the mechanism of spin-electric coupling in a 4f molecular qudit.

Fast and reliable entanglement distribution in quantum networks requires multiplexing to enhance rates and distillation to compensate the loss in fidelity. Classical communication latency associated with both swapping and distillation protocols is a significant hurdle, which the authors address by proposing a class of quasi-local entanglement distribution policies for multiplexed repeater chains.

Clear experimental signatures of fractional statistics in topologically ordered phases have been lacking. Here, the authors predict detectable signatures of non-trivial mutual statistics of fractionalized excitations in gapped topological quantum spin liquids at finite temperature.

The dynamics of quantum states underlies the emergence of thermodynamics and even recent theories of quantum gravity. Now it has been proven that the quantum complexity of states evolving under random operations grows linearly in time.

Control of the interaction between atoms and their neighbours is important to quantum information processing and has been studied using two states. Here the authors demonstrate a more flexible control using a three-state superposition of donors in silicon using THz quantum beat spectroscopy.

Somatosensory hypersensitivity in Fmr-1 knockout mice is thought to arise from an increase in cortical circuit excitability. Here, the authors report that the loss of precision of sensory encoding in the Layer 4 of barrel cortex is the primary developmental circuit alteration that drives the other compensatory circuit dysfunction.

Here, dynamical light squeezing is observed in the emission from two coupled weakly nonlinear populations of exciton-polaritons through ultrafast time-resolved second-order correlation measurements. Full quantum simulations link the squeezing to the periodic bunching observed in the light statistics.

Closed-loop optogenetic stimulation with excitatory opsins enables the precise manipulation of neural dynamics in brain slices from transgenic mice and in anaesthetized non-human primates.

To fulfil the potential of quantum machine learning for practical applications in the near future, it needs to be robust against adversarial attacks. West and colleagues give an overview of recent developments in quantum adversarial machine learning, and outline key challenges and future research directions to advance the field.

Entangled local states can be made capable of violating Bell inequalities via nonlocality activation. Typical theoretical approaches require processing many copies of the original state and performing joint measurements on the ensemble. Here, instead, the authors experimentally demonstrate how to do so using a single copy of the state, broadcasting it to two spatially separated parties within a three-node network.

The creation and manipulation of large quantum states is necessary for quantum information processing tasks. Three-level, four-partite cluster states have now been created in the time and frequency domain of two photons on-chip.

By using a five-qubit error-correcting code with a recently discovered flag protocol, a logical qubit that is operated fault-tolerantly is realized based on solid-state spin qubits in diamond.

Two intriguing manifestations of Hall physics are reported in a topologically insulating heterostructure: a sign-reversal of the anomalous Hall effect and the emergence of a topological Hall effect.

By emulating a 2D hard-core Bose–Hubbard lattice using a controllable 4 × 4 array of superconducting qubits, volume-law entanglement scaling as well as area-law scaling at different locations in the energy spectrum are observed.

Fractional magnetic excitations are thought to exist even in the simplest multi-dimensional spin models, but attention has focused on frustrated systems. Such excitations have now been seen in an unfrustrated two-dimensional quantum antiferromagnet.

Long-range coherent spin-qubit transfer between semiconductor quantum dots requires understanding and control over associated errors. Here, the authors achieve high-fidelity coherent state transfer in a Si double quantum dot, underpinning the prospects of a large-scale quantum computer.

In this alternative approach to quantum computation, the all-electrical operation of two qubits, each encoded in three physical solid-state spin qubits, realizes swap-based universal quantum logic in an extensible physical architecture.

Recovery of skilled motor function in rodents after stroke correlates with the restoration of low-frequency quasi-oscillatory activity in the motor cortex, and neuromodulatory electrical stimulation targeting this activity can further accelerate recovery.

The ability to perform nonlinear feedforward operations - that is, conditional operations controlled by nonlinear function of the measurement outcomes - is still a missing ingredient for measurement-based quantum computation. Here, the authors fill this gap using nonlinear electro-optical feedforward and non-Gaussian ancillary states.

Samarium hexaboride is a candidate topological insulator but recent experiments have found behaviour indicative of a metallic Fermi liquid phase. Here the authors show that the conflicting observations can be accommodated by a model where strong interactions drive the formation of exotic neutral quasiparticles.

Traditional systematic anti-seizure treatments alter brain-wide activity and often carry significant side effects. The authors engineered an inhibitory, acetylcholine receptor-based, chemogenetic tool to suppress targeted neurons, enabling control of chronic seizures in mice.

A quantum many-body system’s equilibrium behaviour is described by its partition function, which is hard to compute. Now it has been shown that the easier task of finding an approximation could define a distinct class of computational problems.

Reconstructing imagined speech from neural activity holds great promises for people with severe speech production deficits. Here, the authors demonstrate using human intracranial recordings that both low- and higher-frequency power and local cross-frequency contribute to imagined speech decoding.

The Jarzynski equality, relating non-equilibrium processes to free-energy differences between equilibrium states, has been verified in a number of classical systems. An ion-trap experiment now succeeds in demonstrating its quantum counterpart.

Molecular magnets are a class of molecule containing multiple magnetic ions whose spins are tightly coupled to give a single 'collective' spin. But it has remained an open question whether the quantum spin states of these molecular entities are sufficiently long-lived to permit useful computation. Pronounced quantum oscillations between the spin states of one such molecular magnet have been observed, indicating that quantum coherence is long-lived.