Volume 15 Issue 8, August 2016

Humankind's aerospace aspirations are placing unprecedented demands on vehicle propulsion systems. Advanced structural ceramics are playing a key role in addressing these challenges.

Metallic materials are fundamental to advanced aircraft engines. While perceived as mature, emerging computational, experimental and processing innovations are expanding the scope for discovery and implementation of new metallic materials for future generations of advanced propulsion systems.

The successful adoption of metallic additive manufacturing in aviation will require investment in basic scientific understanding of the process, defining of standards and adaptive regulation.

David Rugg is the Senior Engineering Fellow in Materials at Rolls-Royce plc. He talks to Nature Materials about the need to understand scientific fundamentals to develop reliable and high-performance materials for jet engines, and the importance of university collaborations.

A rewritable platform for subwavelength optical components is demonstrated by combining surface phonon–polaritons, sustained in a polar dielectric layer, with the switching functionality provided by a phase-change material.

Titanium aluminide alloys are lightweight and have attractive properties for high-temperature applications. A new growth method that enables single-crystal production now boosts their mechanical performance.

An adsorbed polymer directs the photochemical growth of colloidal Au single-crystal nanoprisms following visible metal excitation.

Classical ionic conduction through an inorganic monolayer nanopore is analogous to the quantum-mechanical phenomenon of electronic Coulomb blockade in quantum dots.

Substrates with curved edges induce the reprogramming of cancer cells into a stem-cell-like phenotype.

Synthetic elastomers designed to mimic the functional properties of human skin show potential applications in cosmetics, topical drug delivery and wound dressings.

Charge-density-wave formation in YBa₂Cu₃O_6+δ (δ ∼ 1) is enhanced at the interface with the metallic ferromagnet La_2/3Ca_1/3MnO₃. This long-range proximity effect—it persists over several tens of nm—is claimed to have an electronic origin.

The transition from a polaronic to a metallic state as the carrier density increases in strontium titanate overlaps with the onset and peak of the bulk superconducting behaviour.

2D surface plasmon polaritons are used to probe the domain-wall solitons in bilayer graphene; near-field infrared nanoscopy reveals various domain-wall structures in mechanically exfoliated graphene bilayers.

The dispersion of metal–organic framework nanocrystals within a polyimide yields membranes for selective chemical separations with strong resistance to plasticization.

Ionic Coulomb blockade—the ionic counterpart of the electronic Coulomb blockade—has been observed in a single subnanometre MoS₂ pore junction.

Experiments with engineered hydrogels show that the geometry of the interface at the perimeter of tumour tissue can guide cancer cells towards a stem-cell-like state.

A new pulsed ferromagnetic resonance method allows efficient spin injection and detection at room temperature through the inverse spin Hall effect, even in organic semiconductors with weak spin–orbit coupling such as C₆₀.

Optically rewritable surface phonon–polariton resonators are demonstrated in a system combining phase-change materials that can reversibly switch between amorphous and crystalline phases, with polar crystals that support surface phonon–polaritons.

Increasing the temperature of jet engines requires materials that are stable against degradation. Towards this goal, growth of TiAl alloys with high strength and ductility, as well as superior creep resistance, is reported at high temperatures.

Discharge in lithium–air batteries can be triggered by using solvents or salts that dissolve LiO₂ intermediate. Adding DBBQ to a weakly solvating electrolyte solution can help O₂ reduction to Li₂O₂ in solution and enhance electrochemical performance.

Plasmon-mediated growth of Au nanoprisms is demonstrated by using polyvinylpyrrolidone as surfactant, which extends the lifetime of the plasmon-generated hot electrons and makes them available to reduce Au precursors from solution.

Small molecules diffusing into a thin film of thiophene-based conjugated polymers act as p-type dopants without altering the ordered microstructure of the film. As a result, free-electron-like charge transport is also observed at high doping levels.

By means of a model of calcite single crystals containing high and tunable amounts of occluded amino acids, the hardness of the crystals can be quantitatively correlated with their composition.

A skin-conforming crosslinked polymer layer formulated for easy topical application mimics the properties of normal, youthful skin and improves the appearance of herniated lower eyelid fat pads.