Nature Physics April Issue

TABLE OF CONTENTS April 2013 Volume 9, Issue 4 Editorial Commentary Thesis Research Highlights News and Views Letters Articles Advertisement Precision measurement and control solutions for cryogenics and materials research. Lake Shore provides cryogenic temperature sensors and instrumentation, magnetic test and measurement systems, and probe stations to customers in academic, government, aerospace, and commercial research institutions. Find the latest company news and product tips on the Lake Shore blog. Subscribe   Facebook   RSS   Recommend to library   Twitter   Advertisement Subscribe to Nature Physics today! For top-quality research in all areas of pure and applied physics choose Nature Physics. Subscribe online here   Editorial Top All must have prizes   p199 doi:10.1038/nphys2608 Millions of dollars of prize money are up for grabs in fundamental physics, through an entrepreneur-funded scheme that should complement, rather than challenge, the Nobel awards. Commentary Top The parallel approach   pp200 - 202 Massimiliano Di Ventra and Yuriy V. Pershin doi:10.1038/nphys2566 A class of two-terminal passive circuit elements that can also act as memories could be the building blocks of a form of massively parallel computation known as memcomputing. Thesis Top What happens if...?   p203 Mark Buchanan doi:10.1038/nphys2596 Research Highlights Top Actin up | Free ride for quantum theory | One man's trash | Four's a crowd | Cool me down News and Views Top Particle physics: Theory with a twistor   pp205 - 206 Andrew Hodges doi:10.1038/nphys2597 A reworking of the theory of particle interactions — the same theory but rendered in a new form based on twistor geometry — is likely to have wide implications for physics, including the reformulation of gravity. Robert C. Richardson: Cool new world   p206 May Chiao doi:10.1038/nphys2598 Fluid dynamics: Lord Kelvin's vortex rings   pp207 - 208 Daniel P. Lathrop and Barbara Brawn-Cinani doi:10.1038/nphys2577 Linking two smoke rings or tying a single ring into a knot is no easy feat. Such topological vortices are now created in water with the aid of specially printed hydrofoils. See also: Article by Kleckner & Irvine Donald A. Glaser: Brilliant bubbles   p208 Alison Wright doi:10.1038/nphys2601 Quantum transport: Spins on the move   pp209 - 210 Patrick Windpassinger doi:10.1038/nphys2568 Recently developed experimental and theoretical tools uncover the complex and unexpected behaviour of impurities propagating through an ensemble of ultracold atoms. See also: Article by Fukuhara et al. Organic spintronics: Inside the interface   pp210 - 211 Valentin Alek Dediu doi:10.1038/nphys2569 A snapshot of electrons crossing a metal/organic interface provides a better understanding of spin filtering and hints at new directions for designing spintronic devices. See also: Article by Steil et al. Fundamental physics: All the world's a lab   p211 David Gevaux doi:10.1038/nphys2599 Complex networks: A winning strategy   pp212 - 213 Raissa M. D'Souza doi:10.1038/nphys2571 Introducing connections between two distinct networks can tip the balance of power — at times enhancing the weaker system. The properties of the nodes that are linked together often determine which network claims the competitive advantage. See also: Letter by Aguirre et al. Physics JOBS of the week Physics Professor in Crystallography University of Sao Paulo- Physics Institute Postdoc position in Quantum Divice Physics Chalmers University of Technology Marie Curie Early Stage Researchers / PhD Students in Physics The University of Nottingham, School of Physics and Astronomy Physics of Blood Platelets University of Göttingen, Germany Faculty Position in Physics Alfaisal University More Science jobs from Letters Top Nanoscale magnetic imaging of a single electron spin under ambient conditions   pp215 - 219 M. S. Grinolds, S. Hong, P. Maletinsky, L. Luan, M. D. Lukin, R. L. Walsworth and A. Yacoby doi:10.1038/nphys2543 A magnetometer focused on nitrogen-vacancy centres in diamond can image the magnetic dipole field of a single target electron spin at room temperature and ambient pressure. Anisotropic impurity states, quasiparticle scattering and nematic transport in underdoped Ca(Fe1-xCox)2As2    pp220 - 224 M. P. Allan, T-M. Chuang, F. Massee, Yang Xie, Ni Ni, S. L. Bud'ko, G. S. Boebinger, Q. Wang, D. S. Dessau, P. C. Canfield, M. S. Golden and J. C. Davis doi:10.1038/nphys2544 When CaFe2As2 is lightly doped with Co an electronic liquid-crystalline state emerges, which becomes the 'parent' state of high-temperature superconductivity in this ferropnictide. A spectroscopic imaging study shows that the 'nematic' order is likely to be an artefact of the doping itself. Electrically tunable transverse magnetic focusing in graphene   pp225 - 229 Thiti Taychatanapat, Kenji Watanabe, Takashi Taniguchi and Pablo Jarillo-Herrero doi:10.1038/nphys2549 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. Successful strategies for competing networks   pp230 - 234 J. Aguirre, D. Papo and J. M. Buldú doi:10.1038/nphys2556 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. See also: News and Views by D'Souza Articles Top Quantum dynamics of a mobile spin impurity   pp235 - 241 Takeshi Fukuhara, Adrian Kantian, Manuel Endres, Marc Cheneau, Peter Schauβ, Sebastian Hild, David Bellem, Ulrich Schollwock, Thierry Giamarchi, Christian Gross, Immanuel Bloch and Stefan Kuhr doi:10.1038/nphys2561 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. See also: News and Views by Windpassinger Spin-dependent trapping of electrons at spinterfaces   pp242 - 247 Sabine Steil, Nicolas Groβmann, Martin Laux, Andreas Ruffing, Daniel Steil, Martin Wiesenmayer, Stefan Mathias, Oliver L. A. Monti, Mirko Cinchetti and Martin Aeschlimann doi:10.1038/nphys2548 Understanding the origin of spin filtering in metal/organic interfaces is important for the control of spin injection in organic semiconductors. A time-resolved photoemission experiment shows that spin filtering can be explained by the trapping of electrons in spin-dependent potentials at the interface. See also: News and Views by Dediu Photoexcitation cascade and multiple hot-carrier generation in graphene   pp248 - 252 K. J. Tielrooij, J. C. W. Song, S. A. Jensen, A. Centeno, A. Pesquera, A. Zurutuza Elorza, M. Bonn, L. S. Levitov and F. H. L. Koppens doi:10.1038/nphys2564 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. Creation and dynamics of knotted vortices   pp253 - 258 Dustin Kleckner and William T. M. Irvine doi:10.1038/nphys2560 Linking 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. See also: News and Views by Lathrop & Brawn-Cinani Top   Advertisement Want access to the best research in pure and applied physics? Nature Physics publishes papers of the highest quality and significance whilst covering the entire spectrum of physics. Recommend Nature Physics to your library using our library recommendation form.   Natureevents is a fully searchable, multi-disciplinary database designed to maximise exposure for events organisers. The contents of the Natureevents Directory are now live. The digital version is available here. Find the latest scientific conferences, courses, meetings and symposia on natureevents.com. For event advertising opportunities across the Nature Publishing Group portfolio please contact natureevents@nature.com More Nature Events

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