Nature Physics

This month we celebrate Nature Physics' twentieth birthday, consider the flexoelectricity of water ice, and feature a Perspective on chiral phonons. Have a look at go.nature.com/NPoct25

Deviations from the textbook current–phase relationship of a Josephson junction can arise from the intrinsic physics of the junction, but also from the inductance of metallic traces. Now a scheme has been developed to distinguish these cases. nature.com/articles/s4156…

Non-Hermitian systems support non-trivial topological effects, yet eigenvalue braiding remains difficult to control and observe. Now, active tuning of laser modes enables programmable and directly observable braiding on an integrated photonic chip. nature.com/articles/s4156…

How angular momentum is exchanged and conserved among lattice modes has been difficult to measure experimentally, but has now been observed via a coherent three-phonon scattering process in a topological insulator. nature.com/articles/s4156…

Massive spatial superpositions are a resource for quantum interferometry, but it has been hard to generate them beyond single atoms. Now spatially entangled massive states are realized through the tunnelling of atomic clusters in optical lattices. nature.com/articles/s4156…

A tunable artificial crystal in a shallow GaAs quantum well is shown to enable interaction-driven insulating behaviour. Electrostatic control tunes the band structure from graphene-like to kagome-like bands. nature.com/articles/s4156…

Transport of charges has been widely studied in 2D moiré materials. However, charge-neutral collective excitations are difficult to access, especially when they are decoupled from charged quasiparticles. Now they are observed in a moiré homobilayer. nature.com/articles/s4156…

Coupling semiconductor qubit devices to microwave resonators provides a way to transfer quantum information over long distances. A flopping-mode qubit that combines strong coupling to photons with good coherence properties has now been demonstrated. nature.com/articles/s4156…

Higher-order interactions in quantum harmonic oscillator systems can result in useful effects, but they are hard to engineer. An experiment on a single trapped ion now demonstrates how spin can mediate higher-order nonlinear bosonic interactions. nature.com/articles/s4156…

Symmetry rules usually prevent interactions between distinct vibrational modes. Now it is shown that charge order fluctuations can mix modes, enhancing the chiral lattice response in a ferroaxial electronic crystal. nature.com/articles/s4156…

The mechanical stability of proteins affects their import into the nucleus. Now it is shown that protein transport in and out of the nucleus depends on the local mechanostability of the protein cargo. nature.com/articles/s4156…

During development, cells acquire their identity—a process that depends on epigenetic modifications such as methylation. Now, a statistical physics analysis of methylation helps explain embryonic symmetry breaking. nature.com/articles/s4156…

Quantum simulation of equilibrium many-body systems requires the ability to sample from the thermal distribution of quantum states. An algorithm has now been proven to be an appropriate quantum analogue to classical Monte Carlo methods. nature.com/articles/s4156…

Argon-42 is a background in experiments that search for dark matter or neutrinoless double-beta decay. Now, the isotope’s abundance is measured by combining a laser-based atom trapping technique with isotope pre-enrichment. nature.com/articles/s4156…

If a surface is hot enough, a liquid droplet can develop an insulating vapour layer that makes it levitate — the Leidenfrost effect. A solid structure of liquid-filled capillaries is now shown to display this effect at much lower temperatures. nature.com/articles/s4156…

Exploiting the differences between quantum and classical physics typically requires nonlinear devices. Quantum nonlinear effects have now been demonstrated in a nanomechanical resonator due to strong coupling with an intrinsic two-level defect. nature.com/articles/s4156…

The isomeric state of thorium-229, a candidate for nuclear clocks, can decay through internal conversion and radiative decays. Now experiments suggest indirect evidence for a higher-order decay process through an electronic transition. nature.com/articles/s4156…

Controlling the dynamics of magnons at terahertz frequencies is important for fast and efficient information processing devices. Now optical excitation is shown to enable ultrafast manipulation of magnon spectra in an insulating antiferromagnet. nature.com/articles/s4156…

It is unclear whether the superconducting pairing in moiré graphene is driven primarily by electronic interactions. Now it is shown that these interactions may play a role in both mediating and screening the pairing. nature.com/articles/s4156…

Physical networks can learn to accomplish tasks on the fly by adjusting their internal parameters. Now it is shown that such physical learning can be achieved in metamaterials that can learn to change shape. nature.com/articles/s4156…

Controlling the rotational motion of nanoscale objects by trapping and cooling is a prerequisite for exploring quantum rotational phenomena. Now, two orthogonal librational modes of a levitated nanorotor are cooled into their quantum ground state. nature.com/articles/s4156…