Browse Physics

Erik Sjöqvist, Physics 1, 35 (2008) – Published November 17, 2008

Quantum Information

Large-scale quantum computers are hard to construct because quantum systems easily lose their coherence through interaction with the environment. Researchers have tried to avoid this problem by using geometric phase shifts in the design of quantum gates to perform information processing. Experiments and simulations have shown that these gates may be tolerant to certain types of faults, and may therefore be useful for robust quantum computation.

Published November 17, 2008

Semiconductor Physics

The transport anomalies found in a bismuth alloy under moderate magnetic field might be the signature of unexpected many-body physics.

Published November 17, 2008

Mesoscopics

Researchers report the observation of a Kondo effect when charge and spin on a double quantum dot system are entangled.

Published November 12, 2008

Nanophysics

Individual molecules can be accurately positioned using a scanning tunneling microscope tip by transferring the energy of internal molecular vibrations into a controlled translational motion.

Published November 12, 2008

Mesoscopics

Researchers explore how the excitonic condensate phase in a bilayer electron gas depends on the relative electron densities of the two layers.

Christoph Bruder, Daniel Loss, Physics 1, 34 (2008) – Published November 10, 2008

Quantum Information

Quantum measurements are conventionally thought of as irretrievably “collapsing” a wave function to the observed state. However, experiments with superconducting qubits show that the partial collapse resulting from a weak continuous measurement can be restored.

Published November 10, 2008

Nanophysics

The rotation of individual large molecules adsorbed onto a gold surface has been observed with a scanning tunneling microscope.

Published November 10, 2008

Plasma Physics

The same instability that is observed in hot plasmas, such as those created in spacecraft ion thrusters, is also found in an ultracold xenon plasma.

Published November 6, 2008

Optics Quantum Mechanics

The optical equivalent of electron oscillations in periodic lattices has now been described by a fully quantum mechanical theory.

Jonathan Sun, Physics 1, 33 (2008) – Published November 3, 2008

Nanophysics Spintronics

If a magnet is small enough, an electric current carrying polarized spins can flip it around. Scientists are finding clever ways to control this spin-torque effect precisely, both for when it is wanted and when it is not.

Published November 3, 2008

Cosmology

At the current time, we cannot tell if Einstein’s cosmological constant—or some other theory—is the correct description for dark energy in the Universe. A proposed measure based on existing data may help us to better distinguish these ideas.

Published November 3, 2008

Graphene Mesoscopics

Experiments suggest that one-dimensional behavior is reflected in the transport properties of graphene nanoribbons.

Published October 30, 2008

Atomic & Molecular Physics Optics

Successive and rapid measurements of a quantum system can prevent it from evolving in time. This quantum Zeno effect has now been demonstrated for light inside a cavity.

Suckjoon Jun and Nick Rhind, Physics 1, 32 (2008) – Published October 27, 2008

Biological Physics

Genome replication originates at random places along the DNA strand, yet replication of the genetic material finishes within a defined time. A model based on phase-transition kinetics in condensed-matter systems explains how this just-in-time replication can happen.

Published October 27, 2008

Quantum Mechanics

When two bulk objects are separated by a sufficiently small distance, quantum fluctuations in the electromagnetic field give rise to Casimir forces between them. Two papers explore how these forces are affected by the electrical properties of the materials.

Published October 27, 2008

Particles & Fields

Researchers propose that the supersymmetric partners of the top and bottom quarks are spin 1 instead of spin 0.

Todd Squires, Physics 1, 30 (2008) – Published October 20, 2008

Fluid Dynamics Biological Physics

Some of the most ingenious ideas for designing microfluidic systems come from observing plants and animals. A study that quantifies the protein-driven helical flow of liquid in large plant cells, for instance, may well inspire micron-scale liquid mixers and sensors.

Carlos Barceló, Physics 1, 31 (2008) – Published October 20, 2008

Cosmology

The universe we see today is the result of mass-energy fluctuations during the rapid inflationary expansion that followed the big bang. A new approach to analyzing those fluctuations brings theory into better alignment with observational data.

Published October 20, 2008

Superconductivity

After the discovery of superconductivity in doped sodium cobaltate, numerous measurements contributed to mapping out the various magnetic and electronic phases that occur in this material. Now, the report of a new phase diagram may challenge the previous version.

Michelle Johannes, Physics 1, 28 (2008) – Published October 13, 2008

Superconductivity

The discovery of superconductivity in iron-based compounds with a similar, but simpler, structure to the iron-pnictides could provide an important testing ground for unconventional superconductivity.

Scott Pratt, Physics 1, 29 (2008) – Published October 13, 2008

Particles & Fields Nuclear Physics Interdisciplinary Physics

Energetic particle jets created in relativistic heavy-ion collisions might create detectable shock waves as they travel through the quark-gluon plasma.

Joseph J. Niemela, Physics 1, 26 (2008) – Published October 6, 2008

Superfluidity Quantum Mechanics Fluid Dynamics

Images of vortex motion in superfluid helium reveal connections between quantum and classical turbulence and may lead to an understanding of complex flows in both superfluids and ordinary fluids.

Rembert Duine, Physics 1, 27 (2008) – Published October 6, 2008

Atomic & Molecular Physics

Spin dependence of atomic and electronic interactions can give rise to propagating regions of aligned spins in solids called spin waves. These have now been observed in a gas of ultracold fermionic atoms.

Published October 6, 2008

Interdisciplinary Physics Statistical Mechanics

How the structural organization of a network evolves as it is observed on larger and larger scales remains an open question. Now, a general and systematic approach to answer this question may be in sight.

Published October 6, 2008

Magnetism Spintronics

From conservation laws to selection rules, symmetry arguments have long been revered for their far-reaching consequences in physics. Now they point to an effective spin-orbit coupling in antiferromagnetic conductors.