Volume 16 Issue 1, January 2020

Synchronization of biochemical oscillators that are responsible for biological rhythms costs free energy. This theoretical result suggests that part of the adenosine triphosphate molecules consumed by a Kai oscillator is necessary for synchronization.

An experiment using ultrafast light pulses demonstrates how to induce a transient chiral electron state in a trivial semimetal.

It is generally difficult to know in advance if a sheet of paper can be folded into an origami shape, but for quadrilateral crease patterns a tiling approach can identify all possible ways of folding them.

The ferromagnetism of iron has been known for millennia. Now a rotational form of spontaneous crystallographic ordering has been discovered. This touches upon fundamental questions about the relation between symmetry, structure and order in matter.

Electrons driven through a suspended carbon nanotube by a constant bias excite mechanical vibrations — including self-sustaining oscillations — and, in some cases, even suppress them down to only a few quanta.

Physical forces have a profound influence on bacterial cell function and physiology. The new tools of nanophysics are bringing to light a tight connection between biomolecular mechanisms and mechanical forces in bacterial cell division.

A new class of inequalities known as thermodynamic uncertainty relations provides quantitative tools for the description of physical systems out of equilibrium. A perspective is offered on these results and their future developments.

Strongly interacting bosons in an optical lattice exhibit anomalous subdiffusive evolution when subjected to a dissipative process. The experimental observations are attributed to a mechanism termed ‘interaction-impeding of decoherence’.

A technique analogous to angle-resolved photoemission spectroscopy used in materials characterization has been developed for interacting Fermi gases in an optical lattice, providing information on the single-particle excitations in a many-body system.

The back-action of electrons can cool a nanomechanical oscillator to a few-quantum state when a current flows through a suspended nanotube. The electron back-action, which is attributed to an electrothermal effect, also induces self-oscillations.

A transient topological response in graphene is driven by a short pulse of light. When the Fermi energy is in the predicted band gap the Hall conductance is around two conductance quanta. An ultrafast detection technique enables the measurement.

The authors use optical spectroscopy to show that RbFe(MoO₄)₂ hosts a ferro-rotational phase. This is the final form of ferroic order to be observed.

Scanning tunnelling microscopy and spectroscopy study of the conductive edge state in a two-dimensional topological insulator reveals the interplay of topology and electronic correlations.

High-energy-resolution spectroscopic measurements performed on the Kondo insulator SmB₆ reveal the presence of correlation-driven heavy surface states—the heavy Dirac fermions—and shed light on the search for the correlated topological materials.

Atomic force microscopy reveals that the accumulation of mechanical stress works together with enzymatic activity to ensure the rapid cleavage of dividing bacteria.

The crease patterns for origami-based mechanical metamaterials can fold into myriad 3D shapes, but predicting foldability is no simple task. A framework for designing foldable patterns offers a neat alternative to extensive computer optimization.

Electro-optomechanical conversion between optical and microwave photons is achieved with minimal added noise by cooling the mechanical oscillator to its quantum ground state. This has potential for future coherence-preserving transduction.

In a nanobeam that is strongly coupled to a single-electron transistor, electron tunnelling back-action induces self-sustaining mechanical oscillations. This oscillator can be compared to a phonon laser and can be stabilized.

Little is known about how edge states in topological materials interact with each other. Here, a quantum spin Hall insulator is used to show that when edge states are brought close together, additional gaps appear in the spectrum.

Using sulfur doping and pressure, the authors separate the nematic and magnetic phase transitions in FeSe. They find that a Lifshitz transition sits between two independent superconducting domes where nematic critical fluctuations remain finite.

The energy cost for the synchronization of biochemical oscillators is determined under general conditions. This framework reveals a relationship between the KaiC ATPase activity and the synchronization of the KaiC hexamers.

A platform for probing the mechanics and migratory dynamics of a growing model breast cancer reveals that cells at the invasive edge are faster, softer and larger than those in the core. Eliminating the softer cells delays the transition to invasion.

Working in a Mexican restaurant during his teenage years, Mark Buchanan discovered his love for jalapeños. Since then he has climbed higher and higher on the Scoville scale.