Reviews & Analysis

Landau’s theory of Fermi liquids predicts that impurities embedded in a Fermi sea of atoms form quasiparticles called polarons that interact with one another via the surrounding medium. Such mediated polaron–polaron interactions have been directly observed and are shown to depend on the quantum statistics of the impurities.

A nonlinear optical approach has now enabled picosecond control of a complex band structure, driving a non-Hermitian topological phase transition across an exceptional-point singularity.

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.

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.

Currently, a general framework explaining the fundamental dynamic transitions from solid to fluid of mechanically probed soft materials is lacking. Now, a unifying van der Waals-like model is proposed that describes the dynamic solid–liquid transition in the rheology of these materials.

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.

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.

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.

When a system is driven across a second-order phase transition, defects can form because it cannot respond quickly enough to the new conditions. The Kibble–Zurek mechanism explains this physics, and has now been invoked for Ising-type domains.

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.

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.

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.

Describing interdependencies and coupling between complex systems requires tools beyond what the framework of single networks offers. This Review covers recent developments in the study and modelling of multilayer networks.

The guiding of magnetic fields by soft ferromagnetic solids is well known and exploited in magnetic shielding applications. Now, ferroelectric nematic liquids are shown to analogously guide electric fields.

An experimental approach enables the observation of the microscopic details of the relaxation of a highly equilibrated glass back to the liquid phase in real time. This points to a scenario where devitrification proceeds via localized seeds separated by macroscopic length scales.