News & Views

In nanoporous solids, optimizing both the size of the pores and the strength of long-range physical properties such as magnetism is not easy. A new approach using radical ions creates a hybrid framework with large pores, in which the reversible and selective loss of a solvent affects the magnetic properties.

A new strategy for mapping the mechanical and magnetic properties of thin films has been used to discover ferromagnetic shape-memory alloys with previously unknown compositions. The results provide new insight into an underlying composition–structure–property relationship of the Ni–Mn–Ga system.

Simple questions in materials science often turn out to have very complex answers. Unravelling the mysteries of how our bones break, on the microscopic scale, is a major task.

Controlling light confinement inside microcavities is crucial to the development of optoelectronic devices such as miniaturized semiconductor lasers. A welcome step in this direction is the successful design of a toroid-shaped microresonator able to trap photons with unprecedented efficiency.

Proposals for carrying out computing at the molecular level generally involve current-carrying circuitry, as in conventional computers. A possible alternative, using an electrostatically operating 'cellular automata', reduces, among other things, the problem of excess heat production.

It is well known that quantum effects become increasingly important as the size of structures is reduced. But the influence of shape on quantum confinement is less appreciated. New data show that shape matters as much as size.

Useful photonic materials must be engineered to high specifications. Microassembly is one solution to building the next generation of photonic crystal structures, as well as many other tiny devices for manipulating light.

Attendees at a recent Materials Research Society symposium on 'bio-inspired' nanomaterials were left to wonder: of biotechnology and nanotechology, which will have a greater impact on the other?

Fluids that respond to magnetic fields are predicted to display complex behaviour and morphologies. New experiments with colloidal dispersions provide direct evidence for self-assembled chains and networks in such systems.

When polymer scientists are asked to select goals for the development of polymer nanostructures and mesoscale engineering, they find self-organization is an important task for scientists and polymers alike.

Nanocrystalline alloys with grain sizes less than 100 nanometres are very strong, but tend to fail rapidly during plastic deformation. A new composite alloy with an unusual microstructure is able to achieve high plasticity by controlling the instabilities responsible for early failure.

A contact-free method for generating precise patterns in polymers is an exciting advance in soft lithography. By exploiting the interactions of two polymers with an electric field, the scale of the patterns can be reduced still further.

Owing to their exceptional stiffness and strength, some of the first materials to use them were reinforced polymer composites. As toughening agents, carbon nanotubes now face a bigger challenge — reinforcing brittle ceramics.

Photonic crystals can manipulate the flow of light, making them attractive materials for new types of optical components. The ability to tune the optical properties of a photonic crystal over femotosecond timescales adds to their technological appeal.

A microporous substance that expands under external hydrostatic pressure is unexpected. Even more surprising is one that can retain its expanded volume after release of the pressure. A zeolite has been found to do just that.

Surfaces are special states of matter. New experiments show that the non-ideal behaviour of nanoclusters on the surface of a catalyst strongly affects their tendency to form larger clusters, and therefore the catalyst's performance.

Future computers will require nanoscale transistors with high-dielectric-constant gate oxides. Carbon nanotube transistors integrated with ZrO₂ gate oxides emerge as very promising candidates.