Volume 19 Issue 12, December 2023

Invest in fostering a culture of collaboration to help break down barriers between disciplines.

Creating a common culture and language for successful collaboration across disciplines benefits both researchers and scientific discovery.

Multidisciplinary residential programmes and workshops help advance all the fields involved.

Macroscale analogies are a powerful conceptual tool with which we can gain insight into the structures and processes of the microscopic world of cell biology.

Fluid flows play a key part in living systems. Cross-disciplinary engagement between fluid physics and biology greatly benefits both fields.

Annually, the European Research Council (ERC) and the National Science Foundation (NSF) allocate resources to promote research excellence in Europe and the USA. We observe that European Union (EU)-based researchers rely strongly on United States (US) collaborations to secure top EU funding, while the reverse is much less common.

Measurements of two neighbouring silicon-based qubits show that the charge noise they each experience is correlated, suggesting a common origin. Understanding these correlations is crucial for performing error correction in these systems.

The simulation of open quantum many-body systems is one of the hardest tasks in computational physics. Now, quantum computers are close to answering crucial questions for such systems in a regime that classical computers cannot reach.

Understanding the mechanism underlying light-induced superconductivity could help manifest it at higher temperatures. Experiments now show that the excitation of a specific phonon leads to a resonant enhancement of this effect in K₃C₆₀.

Understanding lattice-geometry-driven electronic structure and orbital character in a titanium-based superconducting kagome metal provides insights into the non-trivial topology and electronic nematicity of correlated quantum matter.

A trilayer copper oxide superconductor, which exhibits the highest superconducting critical temperature as a function of the number of copper–oxygen planes, is shown to have unusual doped hole distribution and interaction between the planes.

Hubbard excitons are elusive quasiparticles that are predicted to form in strongly correlated insulators. Detecting their internal structure and dynamics clarifies the involvement of spin fluctuations in their binding and recombination processes.

Disordered systems that are far from equilibrium relax slowly towards their equilibrium. Now, we learn that the irreversible plastic deformations that form the wrinkles of a crumpled sheet result in a complex energy landscape that ages logarithmically.

Permanent deformation in solids results from atoms not aligning with the external stress causing the deformation. Detecting such non-affine atomic rearrangements and connecting them to measurable mechanical effects is now shown to be feasible by means of high-energy X-ray diffraction.

The liquid-crystal-like order of cells in epithelial tissues aids rearrangements, but there is disagreement over the dominant liquid crystal phase. Now, a unified approach reveals that two distinct symmetries dominate at different scales.

Local thermodynamic measurements of a twisted transition metal dichalcogenide heterostructure reveal competition between unconventional charge order and Hofstadter states. This results from the presence of both flat and dispersive electronic bands, whose energetic ordering can be experimentally tuned.

An approach combining single-cell imaging, agent-based simulations, and continuum mechanics theory is used to observe the effect of environmental stiffness on biofilm development. These measurements indicate that confined biofilms behave as active nematics, in which the internal organization and cell lineage are controlled by the shape and boundary of the biofilm.

Cells in a tissue layer arrange themselves in orientationally ordered structures. Now two types of liquid crystalline order have been shown to coexist, with nematic order dominating large length scales and hexatic order dominating small length scales.

Physical realizations of qubits are often vulnerable to leakage errors, where the system ends up outside the basis used to store quantum information. A leakage removal protocol can suppress the impact of leakage on quantum error-correcting codes.

It is hoped that simulations of molecules and materials will provide a near-term application of quantum computers. A study of the performance of error mitigation highlights the obstacles to scaling up these calculations to practically useful sizes.

Errors in a quantum computer that are correlated between different qubits pose a considerable challenge for correction schemes. Measurements of noise in silicon spin qubits show that electric field fluctuations can create strongly correlated errors.

Quantum computers may help to solve classically intractable problems, such as simulating non-equilibrium dissipative quantum systems. The critical dynamics of a dissipative quantum model has now been probed on a trapped-ion quantum computer.

Material characterization of liquids in extreme thermodynamic conditions is a challenging technical problem. Brillouin scattering metrology in an optical fibre design with a sealed liquid core now enables spatially resolved temperature and pressure measurements, using carbon disulfide as an example.

The application of high-harmonic spectroscopy to liquid samples shows that the cut-off energy is a material characteristic. This approach may also give experimental access to electron mean free paths.

There is evidence that K₃C₆₀ can host a photo-induced superconducting state. Now, resonant excitation at low frequencies allows this phenomenon at room temperature and low pumping fluence.

The origin of nematicity in kagome superconductors has been hard to explain due to other entangled phases. Now, the role of orbital hybridization and coupling is revealed to induce electronic nematicity in the kagome superconductor RbTi₃Bi₅.

Observation of a faint Fermi surface inside the pseudogap of an electron-doped cuprate suggests that Cooper pairing is mediated by antiferromagnetic spin fluctuations.

Measurements of the electronic structure of a trilayer cuprate superconductor suggest that its high critical temperature is explained by the different doping levels of the layers. The combination of underdoped inner layer and overdoped outer layers supports superconductivity.

One-dimensional chains of magnetic adatoms on the surface of a superconductor have been claimed to host topological states. Now, this idea is extended to two-dimensional systems.

Observations of the conversion of orbital angular momentum into charge indicate that the orbital degree of freedom can provide a channel for information storage and processing.

The interplay between flat and dispersive bands in moiré materials has not yet been examined in detail. Now, the phase diagram of a transition metal dichalcogenide bilayer shows correlated states arising from both types of band.

Phonons that carry a large magnetic moment may be helpful for creating spintronic devices. Now this phenomenon is observed in an antiferromagnet and is enhanced by the critical fluctuations associated with a phase transition.

Hole and particle-like quasiparticles of a Mott insulator can pair into excitonic bound states. Now, time-resolved measurements of Sr₂IrO₄ show signs of an excitonic fluid forming from a photo-excited population of quasiparticles.

Na₃Ni₂BiO₆ with a honeycomb lattice is found to host a one-third magnetization plateau phase signifying frustrated interactions and indicates that Kitaev interactions can be realized in high-spin magnets.

Many complex systems relax slowly towards equilibrium after a perturbation, without ever reaching it. Experiments with crumpled sheets now show that these relaxations involve intermittent avalanches of localized instabilities, whose slow-down leads to logarithmic aging.

Resolving the structural changes of a deformed glass on the atomic scale is challenging due to its disordered nature. Now, high-energy diffraction measurements show that non-line-preserving atomic displacements in glasses correlate with structural anisotropy.

The Magnus effect refers to rotating objects developing a lift force when travelling through a fluid. It normally vanishes at microscopic length scales but now a very large Magnus effect is demonstrated for spinning colloids in viscoelastic fluids.

The boson peak refers to an excess in the phonon density of states seen in three-dimensional amorphous materials. Helium-atom scattering experiments have now revealed a boson peak in a two-dimensional material, too, at a frequency similar to that of the bulk material.

Filaments of the FtsZ protein can form chiral assemblies. Now, active matter tools link the microscopic structure of active filaments to the large-scale collective phase of these assemblies.

Wrinkling of cell nuclei is associated with disease. During development, the nucleus behaves like a sheet of paper and the wrinkling amplitude can be manipulated without changing its pattern.

Confined biofilms can shape themselves and their boundary to modify their internal organisation. This mechanism could inform the development of active materials that control their own geometry.

The hectare has a long association with the metric system, but its most recent status has created some ambiguity as to its future application. Richard Brown surveys the lay of the land.