Volume 14 Issue 6, June 2015

It has long been thought impossible for pure metals to form stable glasses. Recent work supports earlier evidence of glass formation in pure metals, shows the potential for devices based on rapid glass–crystal phase change, and highlights the lack of an adequate theory for fast crystal growth.

Recent research has revealed considerable diversity in the short-range ordering of metallic glass, identifying favoured and unfavoured local atomic configurations coexisting in an inhomogeneous amorphous structure. Tailoring the population of these local motifs may selectively enhance a desired property.

There have been a number of attempts to commercialize bulk metallic glass over the past 20 years. William L. Johnson, the Mettler Professor of Materials Science at California Institute of Technology, has been a prominent figure in these efforts and gives Nature Materials his perspective on the topic.

Hybrid perovskite is introduced as a new material for nanowire lasers. One-dimensional nanostructures of these perovskites can be optically pumped to lase with tunable wavelength at relatively low threshold, which marks a step towards their use in integrated photonics.

Implanted spheres with a diameter larger than 1.5 mm escape fibrotic responses, thereby extending the survival time of the encapsulated therapeutic cells.

Now that certified energy conversion efficiencies for perovskite solar cells are above 20%, researchers are exploring other critical areas, such as understanding device hysteresis and film growth, as well as the replacement of lead and the development of tandem cell stacks. Cell stability remains a crucial issue.

Superconducting qubits are used to demonstrate features of quantum fault tolerance, making an important step towards the realization of a practical quantum machine.

Fingerprints of electron pairing in a range of temperature and magnetic field above the bulk superconducting phase transition have been found, which may be evidence for the long-sought 'preformed pairs' expected in strongly coupled or very dilute superconductors.

Optically excited plasmonic nanoparticles can activate chemical reactions on their surfaces. The underlying physical mechanisms responsible for the chemical activity and advances in photocatalysis on plasmonic metallic nanostructures are discussed.

Electron filling causes a reduction of the chemical potential in (Sr_1−x La_x)₃Ir₂O₇, which suggests negative electronic compressibility. Studying the concomitant change of the bandgap provides insight into the physical mechanism behind this effect.

Soft filamentous bundles, including F-actin, microtubules or bacterial flagella, can experience large frictional forces that scale logarithmically with sliding velocity, and such frictional coupling can be tuned by modifying lateral interfilament interactions.

A general memoryless molecular mechanism explains the self-organization of Brownian-like steps into truncated Lévy walks in the classic system of intracellular trafficking.

Little is known about the micromechanisms by which deformation twinning occurs in body-centred cubic crystals. An atomic-scale microscopy study now provides new insight, by the in situ testing of tungsten nanowires.

The thermal conductivity of diamagnetic InSb decreases as a magnetic field is increased at low temperatures and is attributed to local dynamic diamagnetism, bringing forth evidence of the magnetic response of phonons.

A concept for the phase control of the nonlinear susceptibility using the left- and right-circular polarization basis for fundamental and harmonic generated light is introduced and tested using metasurfaces containing plasmonic antennas.

Local oxidation of the methyl groups of self-assembled silane monolayers into carboxylic acid functional groups allows the realization of solid ion-conducting channels, on top of which single layers of metal ions can drift when a voltage is applied.

A flexible n-type material has been developed with a thermoelectric figure of merit of 0.28 at 373 K via the intercalation of organic cations between titanium disulphide monolayers.

Initiated chemical vapour deposition enables the conformal growth of ultrathin insulating polymer layers. These polymer films can be deposited on a broad range of materials used for organic and flexible electronics, including graphene.

A surface-initiated solution growth method is used to synthesize single-crystal nanowires of organic–inorganic perovskite that show very low lasing threshold. Coating the nanowires with metallic films marginally affects the lasing performance.

Implanted spheres of a broad variety of material classes significantly abrogate foreign body reactions and fibrosis in rodent and non-human primates when the spheres are larger than 1.5 mm in diameter.

Metallic glasses attract substantial research efforts, which aim to elucidate their structure, properties and the underpinning factors that control glass formation. This focus issue explores some of the most pressing challenges in our scientific understanding of metallic glasses and provides an outlook on their commercialization.