Research articles

The phase diagram of confined ice is different from that of bulk ice. Simulations now reveal several 2D ice phases and show how strong nuclear quantum effects result in rich proton dynamics in 2D confined ices.

The kernel method in machine learning can be implemented on near-term quantum computers. A 27-qubit device has now been used to solve learning problems using kernels that have the potential to be practically useful.

Light passing through complex media is subject to scattering processes that mix together different photonic modes. This complexity can be harnessed to implement quantum operations.

In quasi-crystals, constituents do not form spatially periodic patterns, but their structures still give rise to sharp diffraction patterns. Now, quasi-crystalline patterns are found in a system of spherical macroscopic grains vibrating on a substrate.

The dynamics of isolated quantum many-body systems far from equilibrium is the object of intense research. Magnetization measurements in a spinor atomic gas now offer a way to classify universal dynamics based on symmetry and topology.

Active flows in biological systems swirl. A coupling between active flows, elongated deformations and defect dynamics helps preserve self-organised structures against disordered swirling.

Non-Hermitian systems can be described in terms of gain and loss with a coupled environment—a hard feature to tune in quantum devices. Now an experiment shows non-Hermitian topology in a quantum Hall ring without relying on gain and loss.

Cell motion along linear confinements is deterministic. Now a model predicts deterministic oscillations in cellular polarization at a Y junction in a set-up with adhesive patterns.

Electric polarization is well defined for insulators but not for metals. Electric-like polarization is now realized via inhomogeneous lattice strain in metallic SrRuO₃, generating a pseudo-electric field. This field affects the material’s electronic bands.

Phases of matter can host different transport behaviours, ranging from diffusion to localization. Anomalous transport has now been observed in an interacting Bose gas in a one-dimensional lattice subject to a pulsed incommensurate potential.

Using the valley degree of freedom in analogy to spin to encode qubits could be advantageous as many of the known decoherence mechanisms do not apply. Now long relaxation times are demonstrated for valley qubits in bilayer graphene quantum dots.

The strengths of connections in networks of neurons are heavy-tailed, with some neurons connected much more strongly than most. Now a simple network model can explain how this heavy-tailed connectivity emerges across four different species.

Coherence between rotational states of polar molecules has previously been limited by light shifts in optical traps. A magic-wavelength trap is able to maximize the coherence time and enables the observation of tunable dipolar interactions.

Topological features such as modularity and small-worldness are common in real-world networks. The emergence of such features may be driven by a trade-off between information exchange and response diversity that resembles thermodynamic efficiency.

Bilayer graphene is known to host states where interactions dominate the electronic behaviour. Now, transport measurements show that this is also true for trilayer graphene and give evidence for ferroelectric states and states with high Chern number.

External driving of qubits can exploit their nonlinearity to generate different forms of interqubit interactions, broadening the capabilities of the platform.

Large quantum computers will require error correcting codes, but most proposals have prohibitive requirements for overheads in the number of qubits, processing time or both. A way to combine smaller codes now gives a much more efficient protocol.

Quantum-correlated photons typically characterize strongly nonlinear quantum emitters. A two-photon correlation spectroscopy method now provides a powerful probe of weakly nonlinear many-body quantum systems.

Quantum coherence is hard to maintain in solid-state systems, as interactions usually lead to fast dephasing. Exploiting disorder effects and interactions, highly coherent two-level systems have now been realized in a rare-earth insulator compound.

Addressing optical transitions at the level of a single site is crucial to unlock the potential of quantum computers and atomic clocks. A scheme based on atom rearrangement now demonstrates such control with demonstrable metrological benefits.