Physics - spotlighting exceptional research

Flipping a photonic shock wave

Shuang Zhang, Xiang Zhang — 2009-11-02T00:00:00-05:00

Čerenkov radiation with the emission cone reversed has been observed in a metamaterial with negative refractive index.

[Physics 2, 91] Published Mon Nov 02, 2009

Can superconducting rings provide clues to the early development of the universe?

John R. Kirtley, Francesco Tafuri — 2009-11-02T00:00:00-05:00

Defects—in the form of vortices in superconductors or “strings” in the fabric of the universe—can reveal the state of a system at the time it was cooled.

[Physics 2, 92] Published Mon Nov 02, 2009

Attoseconds for all

2009-11-02T00:00:00-05:00

An advance in attosecond pulse generation will make it easier to produce a single pulse.

Published Mon Nov 02, 2009

Predicting crystal structures

2009-11-02T00:00:00-05:00

When crystal formation is purely entropy driven, as is the case for superstructures of nanoparticles with hard-sphere interactions, new simulations that can run at finite temperature are needed.

Published Mon Nov 02, 2009

Slipping through blood flow

Howard A. Stone, Alison M. Forsyth, Jiandi Wan — 2009-10-26T00:00:00-04:00

Simulations provide insight into how viscous flow transforms the shapes of red blood cells, which may influence their physiological properties.

[Physics 2, 89] Published Mon Oct 26, 2009

Tensor networks—a new tool for old problems

Subir Sachdev — 2009-10-26T00:00:00-04:00

A new renormalization group approach that maps lattice problems to tensor networks may hold the key to solving seemingly intractable models of strongly correlated systems in any dimension.

[Physics 2, 90] Published Mon Oct 26, 2009

Nearly perfect fluidity

Thomas Schäfer — 2009-10-26T00:00:00-04:00

Is there a fundamental lower bound on viscosity? To answer this question, we can look at the coldest and hottest fluids that laboratories are able to produce.

[Physics 2, 88] Published Mon Oct 26, 2009

An ultracold graphene analog

2009-10-26T00:00:00-04:00

The properties of graphene might be studied from another angle by putting ultracold atoms into a hexagonal optical lattice.

Published Mon Oct 26, 2009

Supercurrents in a junction—it’s all about the timing

2009-10-26T00:00:00-04:00

Microwave-frequency excitation of a superconductor-metal-superconductor junction is used to resolve the dynamic mechanisms behind the temporal response.

Published Mon Oct 26, 2009

Exciting rogue waves

Mattias Marklund, Lennart Stenflo — 2009-10-19T00:00:00-04:00

How freak or rogue waves form in the ocean is not well understood, but new investigations suggest a mechanism for these waves that may also allow formation of high-intensity pulses in optical fibers.

[Physics 2, 86] Published Mon Oct 19, 2009

Spins in cold atoms—what a drag!

Marco Polini, Giovanni Vignale — 2009-10-19T00:00:00-04:00

Interactions among noncondensed bosonic atoms in a trap can cause one species of atoms accelerated by a magnetic field to drag along another species of atoms that would normally not interact with the field.

[Physics 2, 87] Published Mon Oct 19, 2009

Theory tackles strong interactions

2009-10-19T00:00:00-04:00

An alternative approach in density-functional theory addresses the effects of strong correlations in many-particle quantum systems.

Published Mon Oct 19, 2009

The quantum shortcut to a solution

2009-10-19T00:00:00-04:00

A quantum algorithm that uses the solution to a set of linear equations provides an exponential speedup by comparison with classical alternatives.

Published Mon Oct 19, 2009

Geodesic carbon nanodomes

J. O. Sofo, R. D. Diehl — 2009-10-12T00:00:00-04:00

Photoelectron spectroscopy reveals how carbon atoms aggregate to form domelike graphene structures on iridium surfaces.

[Physics 2, 84] Published Mon Oct 12, 2009

Reaching a new resolution standard with electron microscopy

Robert F. Klie — 2009-10-12T00:00:00-04:00

A new approach to reduce spherical and chromatic aberration in electron microscopy allows for low-energy imaging of single-layer boron nitride, a novel 2D nanostructure that is analogous to graphene.

[Physics 2, 85] Published Mon Oct 12, 2009

The rules of disorder

2009-10-12T00:00:00-04:00

Disorder causes an unexpected quantum phase transition in graphene.

Published Mon Oct 12, 2009

The shortest known photon pulses

2009-10-12T00:00:00-04:00

A model of the quark-gluon plasma predicts it could emit the sort of ultrashort light pulses that would be useful for high-speed spectroscopy.

Published Mon Oct 12, 2009

Quasiparticles do the twist

Joel E. Moore — 2009-10-05T00:00:00-04:00

A theoretical analysis of recent experiments suggests that a key feature of a topological quantum computer—the unusual statistics of quasiparticles in the quantum Hall effect—may finally have been observed.

[Physics 2, 82] Published Mon Oct 05, 2009

Protecting quantum superpositions from the outside world

Alexander Lvovsky — 2009-10-05T00:00:00-04:00

An entangled state of six photons could potentially carry quantum information over large distances and between different reference frames.

[Physics 2, 83] Published Mon Oct 05, 2009

Orientation without perturbation

2009-10-05T00:00:00-04:00

Femtosecond light pulses at two different frequencies are effective in aligning and orienting molecules without the need for a strong static field.

Published Mon Oct 05, 2009

Small-scale hydraulics

2009-10-05T00:00:00-04:00

Rotating electric fields can power the flow of water along a nanochannel.

Published Mon Oct 05, 2009

Shifting entropy elsewhere

Dan M. Stamper-Kurn — 2009-09-28T00:00:00-04:00

New methods for lowering the entropy of ultracold gases may allow observation of more subtle quantum materials.

[Physics 2, 80] Published Mon Sep 28, 2009

Large rare patches of order in disordered boson systems

Peter B. Weichman — 2009-09-28T00:00:00-04:00

The existence, through statistical fluctuation, of arbitrarily large regions with a certain order in an otherwise disordered system, allow one to set bounds on various important thermodynamic properties.

[Physics 2, 81] Published Mon Sep 28, 2009

How to accelerate the wall of an optical waveguide

2009-09-28T00:00:00-04:00

By generalizing the idea of a moveable mirror, it may be possible to observe the dynamical Casimir effect.

Published Mon Sep 28, 2009

Electronics without solids

2009-09-28T00:00:00-04:00

The atoms in an optical lattice could form the basis for a complete circuit including a diode or a transistor.

Published Mon Sep 28, 2009

Getting the calcium you need

2009-09-28T00:00:00-04:00

A Bose-Einstein condensate of calcium atoms has been created, the first from alkaline earth elements and potentially useful for stable clocks and precision measurements.

Published Mon Sep 28, 2009

Deconstructing the electron

Thierry Giamarchi — 2009-09-21T00:00:00-04:00

An angle-resolved photoemission spectroscopy study of electron transport along quasi-one-dimensional Mo-O chains of Li_0.9Mo₆O₁₇ reveals puzzling behavior that does not fit within the available one-dimensional theory frameworks and likely points to undiscovered physics.

[Physics 2, 78] Published Mon Sep 21, 2009

The weak and strong ends of a theory

Joseph Minahan — 2009-09-21T00:00:00-04:00

A mathematical formulism makes a step forward in proving the AdS/CFT correspondence that connects quantum mechanics with gravity.

[Physics 2, 79] Published Mon Sep 21, 2009

Drilling for tunable photons in a nanohole

2009-09-21T00:00:00-04:00

The demonstration of photon emission as free-electrons pass through a nanoscale grating could pave the way for a new generation of on-chip tunable light sources.

Published Mon Sep 21, 2009

The long and short of it

2009-09-21T00:00:00-04:00

Ultrafast optical probing of an ionized molecule with different pulse durations reveals details of the dynamics of vibrational excitations.

Published Mon Sep 21, 2009