Articles in 2014

Subradiant states have remained elusive since their prediction sixty years ago, but they have now been uncovered in ultracold molecules, where they could prove useful for ultra-high precision spectroscopy.

Graphene’s electronic properties can be modified by putting it on a substrate. Now it is shown that intercalating a graphene sheet and an iridium substrate with lead islands causes resonances, attributed to a spatial variation of spin–orbit coupling.

Solids embedded with fluid inclusions are intuitively softer than their pure counterparts. But experiments show that when the droplets are small enough, material can become stiffer—highlighting a role for surface tension.

Defects are often introduced to increase the stiffness of three-dimensional materials. Evidence now suggests that the elastic modulus of two-dimensional graphene sheets can also be increased by controlled defect creation.

An experimental study characterizes subradiance—inhibited emission due to destructive interference—in ultracold molecules close to the dissociation limit and shows that it could be used for precision molecular spectroscopy.

Fractional magnetic excitations are thought to exist even in the simplest multi-dimensional spin models, but attention has focused on frustrated systems. Such excitations have now been seen in an unfrustrated two-dimensional quantum antiferromagnet.

Magnetic fields can be used to modify light absorption in chiral media, but the effect is weak, so the potential of this approach has gone largely untapped. Synchrotron radiation may provide a solution, enabling surprisingly strong dichroisms in a molecular helix.

Weak magneto-chiral dichroic effects may explain why biomolecules all have the same chirality, but they are notoriously difficult to observe. Using hard X-rays, strong magneto-chiral dichroism has now been observed in a paramagnetic molecular helix.

The Nernst coefficient is a measure of the transverse thermoelectric effect in a conductor. Superconducting fluctuations magnify this effect but in URu₂Si₂, the million-fold enhancement suggests that the fluctuations have an exotic origin.

Ferroelectric polarization vortices close to a ferroelectric transition turn out to be striking models of the cosmos in which strings are thought to have condensed out of the rapid expansion of the early Universe.

As the debate on immigration in the UK becomes increasingly visceral, British science risks being caught in the crossfire.

The universal challenge.