: Materials Articles
News and Views: Photovoltaics: More solar cells for lessA solar-cell design based on silicon microwires achieves efficient absorption of sunlight while using only 1% of the active material used in conventional designs. Nature Materials, vol. 9 #3, pp183-184 |
News and Views: Magnetization dynamics: Ferromagnets stirred upConflicting observations of the speed at which various ferromagnetic materials respond to an external femtosecond laser excitation have generated considerable controversy. It is now shown that ferromagnets can be divided in two categories, according to the values of specific magnetic parameters. Nature Materials, vol. 9 #3, pp184-185 |
News and Views: Oxide surfaces: Surface science goes inorganicA plethora of chemical tools is necessary for probing the surface reconstruction of a complex metal oxide. Nature Materials, vol. 9 #3, pp185-187 |
News and Views: Topological insulators: Oscillations in the ribbonsThe observation of Aharonov?Bohm oscillations in nanoribbons of Bi2Se3 opens the way for electronic transport experiments in nanoscale three-dimensional topological insulators. Nature Materials, vol. 9 #3, pp187-188 |
News and Views: Multiferroics: A whirlwind of opportunitiesThe formation of vortices in multiferroic hexagonal manganites, where the sign of electric polarization changes six times around the vortex core, points towards the origin of composite multiferroic domain walls. Nature Materials, vol. 9 #3, pp188-190 |
Letter: Transition from a strong-yet-brittle to astronger-and-ductile state by size reductionofmetallicglassesThe mechanical properties of many materials are different on the nanoscale than they are in the bulk. In the case of metallic glasses, nanometre-scale samples show enhanced ductility. This tensile ductility has now been quantified for samples with diameters down to 100?nm, where a new regime of increased ductility during deformation is observed. Nature Materials, vol. 9 #3, pp215-219 |
Letter: Generality of shear thickening in dense suspensionsIn most suspensions viscosity decreases with increasing shear rate. The opposite effect, shear thickening, is a problem for industrial applications. An understanding of how particle interactions in suspensions influence shear thickening may lead to a solution of this problem through the design of smart suspensions. Nature Materials, vol. 9 #3, pp220-224 |
Letter: Aharonov?Bohm interference in topological insulator nanoribbonsThe existence of topological conducting surfaces on insulators has been demonstrated by angular photoemission spectroscopy, but the number of transport experiments on these systems have so far been scarce. Transport evidence of topological surface states is now shown in Bi2Se3 nanoribbons through the observation of Aharonov?Bohm oscillations. Nature Materials, vol. 9 #3, pp225-229 |
Letter: Current-driven spin torque induced by the Rashba effect in a ferromagnetic metal layerControl of magnetization in ferromagnetic metals can be achieved through the spin torque of currents of spin-polarized electrons, usually injected externally. It is now shown that even without this spin-polarized injection, a current can induce strong spin torques through the Rashba effect. The efficiency of this process makes it a realistic candidate for room-temperature spintronic applications. Nature Materials, vol. 9 #3, pp230-234 |
Letter: Many-body effects in electronic bandgaps of carbon nanotubes measured by scanning tunnelling spectroscopyWhy does the bandgap in semiconducting carbon nanotubes depend on the way it is measured? It is now shown that the results obtained by scanning tunnelling spectroscopy are usually influenced by screening, which creates the discrepancy with optical measurements. The results highlight the importance of many-body effects in the electronic properties of carbon nanotubes. Nature Materials, vol. 9 #3, pp235-238 |
Letter: Enhanced absorption and carrier collection in Si wire arrays for photovoltaic applicationsThe use of silicon nanostructures in solar cells offers a number of benefits, such as the fact they can be used on flexible substrates. A silicon wire-array structure, containing reflecting nanoparticles for enhanced absorption, is now shown to achieve 96% peak absorption efficiency, capturing 85% of light with only 1% of the silicon used in comparable commercial cells. Nature Materials, vol. 9 #3, pp239-244 |
Letter: A homologous series of structures on the surface of SrTiO3(110)Resolving the surface structure and chemistry of oxides such as strontium titanate has so far proved difficult. Rings of six or eight corner-sharing TiO4 tetrahedra and a homologous series of surface reconstructions for SrTiO3(110) are now predicted. Nature Materials, vol. 9 #3, pp245-248 |
Letter: Chemically fixed p?n heterojunctions for polymer electronics by means of covalent B?F bondformationCreating p?n junctions using semiconducting polymers has proved to be challenging because of difficulties in depositing semiconducting polymer films. Now, by using a cationic conjugated-polymer electrolyte and a neutral conjugated-polymer layer, devices with a fixed bilayer organic p?n junction and fast response times have been fabricated. Nature Materials, vol. 9 #3, pp249-252 |
