Reviews & Analysis

Materials that exhibit both ferromagnetism and ferroelectricity could be useful, but they are unfortunately very rare. Could a new proposal for combining the two properties point the way forward?

Iron oxide-doped photonic crystals are a simple means to wrap fluid droplets and control their movement. But they are also clever because they can be 'bar-coded' and have in-built sensing capabilities, which makes them exceptional candidates for microfluidic devices.

Supramolecular engineering using self-assembly aims to develop complex functional materials and devices. The fabrication of acentric organic films by physical vapour deposition for electro-optic applications illustrates the potential of such bio-inspired approaches.

The spreading of metallic liquid drops on flat solid metal or ceramic substrates ranges from milliseconds — comparable to room-temperature spreading of water on glass — to hours. This varying timescale can be understood by what happens — or doesn't happen — at the foot of the drop where the liquid surface contacts the substrate.

Magnetic random-access memory (MRAM) has been touted as a universal memory with a wide range of potential applications in portable computers, consumer electronics and wireless devices. The use of certain combinations of materials that can now be deposited as thin-film layers with excellent crystalline order provides a significantly larger signal in the devices, and is expected to help advance the commercialization of MRAM.

Light-absorbing materials can exhibit exceptional photothermal effects as their characteristic dimensions approach the nanoscale. A flash welding technique that exploits the peculiar photothermal response of polyaniline nanofibres opens new avenues for processing and patterning polymer-based materials and devices.

The temperature dependence of the viscosity of most glass-forming liquids is known to depart significantly from the classical Arrhenius behaviour of simple fluids. The discovery of an unexpected correlation between the extent of this departure and the Poisson ratio of the resulting glass could lead to new understanding of glass ageing and viscous liquid dynamics.

Superconductivity and ferromagnetism are two very useful phenomena, but rarely coexist in bulk materials. Bringing them together in artificial hybrid structures produces some unusual results.

A glass transition in amorphous silicon has been surmised but never clearly shown experimentally. The very fast timescale of ion hammering experiments allows observation of the long-sought low-density liquid polyamorph of silicon.

Stethoscopes, loudspeakers, microphones, pressure gauges and many other common devices share a basic mechanism of operation — a pliable membrane deflecting under the influence of an external force. A nanocomposite membrane has now been developed that shows great sensitivity and autorecovery capabilities.

Controlling metal oxidation is an age-old problem and the integrity of the metal–oxide interface is key to long-term material stability. A deeper investigation of this buried interface reveals the processes occurring at the atomic scale, and provides tantalizing clues for alloy design.

The extraordinarily high strength and stiffness of single-walled carbon nanotubes promises a myriad of unique applications, but many of these are reliant on the growth of ultralong, continuous nanotubes. A new synthetic procedure takes us a step closer to this goal.

Chemical immobilization of electro-active enzymes on conducting nanocrystalline-diamond thin films is laying the basis for diamond-based electrochemical biosensors and bio-interfaces.

Describing the structure of amorphous materials such as metallic glasses has been a longstanding problem in materials science. A new technique called fluctuation microscopy allows us to see order on length scales that are difficult to study with traditional scattering techniques.

The coupling of energy to surface-plasmons in the metal contacts of a light-emitting diode is usually considered detrimental to optical efficiency. A new study suggests that the opposite could be true.