Nature Physics - Current issue : March 2013 - Vol 9 No 3
- Space–time resolved
- Solar physics: Cassini shocks
- Graphene: Topological insulator phased in
- Quantum simulators: Spins on a diamond surface
Latest highlights
Current issue
Size and supersize
Thesis by Buchanan"Could mathematical theory explain some of the more ‘living’ features of biological reality? The blue whale, for instance, is the largest of all mammals, and seemingly anomalous in its size... Indeed, [the] calculation of the chance that some oceanic species would be at least as large as the blue whale, given the opposing influences on size, is close to 90%. The chance of there having been a species considerably larger is still appreciable. In our world, at least one species of enormous sea monster is just what we should expect.”
Nature Physics Focus
Complex networks in finance
FocusThe 2008 financial crisis has highlighted major limitations in the modelling of financial and economic systems. However, an emerging field of research at the frontiers of both physics and economics aims to provide a more fundamental understanding of economic networks, as well as practical insights for policymakers. In this Nature Physics Focus, physicists and economists consider the state-of-the-art in the application of network science to finance.
Advance online publication
Topological insulators
Letter by Jozwiak et al.In a topological insulator, the surface-state electron spins are ‘locked’ to their direction of travel. But when an electron is kicked out by a photon through the photoelectric effect, the spin polarization is not necessarily conserved. In fact, the ejected spins can be completely manipulated in three dimensions by the incident photons.
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News and Views by XueAdvance online publication
Fluid dynamics
Article by Kleckner & IrvineLinking two smoke rings or tying a single ring into a knot is no easy feat. Now, however, such topological vortices are created in water using 3D-printed hydrofoils. High-speed imaging shows how the linked rings spontaneously separate, and the knots are able to free themselves. Similar fluid dynamics may also be relevant in plasmas, quantum fluids and optics.
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News and Views by Lathrop & Brawn-CinaniAdvance online publication
Graphene
Article by Tielrooij et al.The efficiency of carrier–carrier scattering in graphene is now experimentally demonstrated. The dominance of this mechanism over phonon-related scattering means that a single high-energy photon could create two or more electron–hole pairs in graphene; an effect useful for optoelectronic applications.
Advance online publication
Graphene
Letter by Taychatanapat et al.Electrons can travel though very pure materials without scattering from defects. In this ballistic regime, magnetic fields can manipulate the electron trajectory. Such magnetic electron focusing, is now observed in graphene. Although the effect has previously been seen in metals and semiconductors, it is evident in graphene at much higher temperatures — including room temperature.
Advance online publication
Complex networks
Letter by Aguirre et al.Networks competing for limited resources are often more vulnerable than isolated systems, but competition can also prove beneficial — and even prevent network failure in some cases. A new study identifies how best to link networks to capitalize on competition.
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News and Views by D'SouzaAdvance online publication
Quantum transport
Article by Fukuhara et al.Understanding the propagation of spin excitations is a difficult problem in quantum magnetism. Using site-resolved imaging in a one-dimensional atomic gas, it is possible to track the dynamics of a moving spin impurity through the Mott-insulator and superfluid regimes.