Browse Physics

Published May 11, 2009

Optics

A unified framework can describe light-matter interactions in a broad range of optomechanical systems, from single laser-cooled atoms to micromechanical mirrors.

Carsten Timm, Physics 2, 35 (2009) – Published May 4, 2009

Magnetism

Transport measurements show evidence of a topologically nontrivial structure—a lattice of skyrmions—in intermetallic MnSi.

Ralf Metzler, Physics 2, 36 (2009) – Published May 4, 2009

Statistical Mechanics Biological Physics

Faster does not mean more precise—a new view of how proteins diffuse and bind to a specific site on the DNA reassesses the role noise plays in the biochemical production line that creates biomolecules from genes.

Bruce Winstein, Kathryn M. Zurek, Physics 2, 37 (2009) – Published May 4, 2009

Particles & Fields Astrophysics Cosmology

New results from the Fermi Gamma-Ray Space Telescope, the most precise to date in the energy range 20 GeV to 1 TeV, should help resolve whether cosmic rays composed of the lightest charged particles, i.e., electrons and positrons, come from dark matter or some other astrophysical source.

Published May 4, 2009

Quantum Mechanics

How screening affects the Coulomb interaction has long been considered a solved problem, but an analysis indicates there is an error in the widely used analytical approach.

Published May 4, 2009

Materials Science Nonlinear Dynamics Quantum Mechanics

Neutron scattering measurements indicate that intrinsic localized modes are found in thermal equilibrium in NaI, a simple ionic crystal.

Sandu Popescu, Physics 2, 32 (2009) – Published April 27, 2009

Optics Quantum Mechanics

In the weird world of quantum mechanics, looking at time flowing backwards allows us to look forward to precision measurements.

David A. Reis, Physics 2, 33 (2009) – Published April 27, 2009

Optics

The observation of squeezed phonons by x-ray diffraction allows researchers to study the interactions between ultrafast lasers and matter in a whole new light.

Marshall Stoneham, Physics 2, 34 (2009) – Published April 27, 2009

Quantum Information Spintronics

Creating a practical solid-state quantum computer is seriously hard. Getting such a computer to operate at room temperature is even more challenging. Is such a quantum computer possible at all? If so, which schemes might have a chance of success?

Published April 27, 2009

Magnetism Superconductivity

Density-functional calculations provide a comprehensive picture of how magnetic order evolves with doping in two iron pnictide compounds.

Published April 27, 2009

Nanophysics

First-principles calculations predict that a thin layer of VO₂ sandwiched between TiO₂ layers has electronic states that exhibit both linear and quadratic dispersion.

Antonio H. Castro Neto, Physics 2, 30 (2009) – Published April 20, 2009

Mesoscopics Graphene

Graphene, believed to be a semimetal so far, might actually be an insulator when suspended freely.

Henning Moritz, Tilman Esslinger, Physics 2, 31 (2009) – Published April 20, 2009

Atomic & Molecular Physics

In a cooled and trapped cloud of ytterbium atoms, the transition from a superfluid to an insulating state has been observed, opening up new possibilities for precision measurements, optical clocks, and quantum computing.

Published April 20, 2009

Gravitation Quantum Mechanics

Finding a quantum theory of gravity remains one of the great unsolved problems in modern physics. Two papers present a quantum gravity theory that, while making different assumptions than general relativity, still reproduces Einstein’s theory in certain limits.

Published April 20, 2009

Optics

Simulations of optical speckle reveal topological scaling laws that apply to a wide range of physical systems.

Published April 20, 2009

Nanophysics

A critical thickness below which thin films of the metallic ferromagnet SrRuO₃ become insulating and lose their ferromagnetic properties has been determined.

Published April 14, 2009

Graphene

Adding a third layer to bilayer graphene leads to a drastic modification of its electronic energy band structure.

Published April 14, 2009

Nanophysics

Coupling two electromechanical oscillators can extend the range over which each individual device is practically useful.

Göran Grimvall, Physics 2, 28 (2009) – Published April 13, 2009

Materials Science

An old problem in solid-state physics is the difficulty of theory to account accurately for the heat capacity of solids close to their melting points.

Dieter Jaksch, Physics 2, 29 (2009) – Published April 13, 2009

Atomic & Molecular Physics

Inelastic light scattering is used to study correlated phases of one-dimensional Bose gases. This spectroscopic technique can distinguish superfluid and insulating phases and allow identification of the transition from one to the other.

Published April 13, 2009

Nuclear Physics

The study of reaction rates between unstable, light nuclei can lead to a better understanding of thermonuclear processes in massive stars and novae.

Published April 13, 2009

Fluid Dynamics Soft Matter

Scaling laws are a useful way to characterize fluid flow over a wide range of flow rates and experimental conditions. Theorists now explain several earlier experiments by finding a scaling law that describes how a liquid-liquid interface changes shape when driven by viscous forces.

Published April 13, 2009

Statistical Mechanics

Cross-correlations in Monte Carlo simulation data can be used for numerical estimates of superior statistical quality.

B. D. Esry, Physics 2, 26 (2009) – Published April 6, 2009

Atomic & Molecular Physics

An ultracold atomic physics experiment reveals universal physics in a four-body system.

Jason R. Petta, Physics 2, 27 (2009) – Published April 6, 2009

Magnetism Semiconductor Physics

A quantum dot refrigerator that cools an electron gas close to 100 mK may allow experimentalists to better probe electron-electron interactions in quantum confined systems.