News & Views in 2006

A breakthrough in the ability to cool high-energy antiproton beams could provide the key to unleashing the potential of the world's highest-energy particle collider.

What happens if the 'weak link' between two superconductors in a Josephson junction is a carbon nanotube, with a limited number of states available for electron transport? A supercurrent flows, but in a unique fashion.

When it comes to superconducting device components, there is no such thing as too thin, but superconductivity has its limits. Now, ultrathin lead films with crystalline perfection have been shown to be able to carry large dissipationless currents down to a thickness of a few monolayers.

Electron spins are traditionally manipulated by a resonant magnetic field, but spin–orbit coupling provides a better option of achieving spin operation, using a resonant electric field. A theoretical treatment now fills in the microscopic detail of this process.

In the early 1900s, the Solvay conferences famously brought together the early protagonists of quantum theory. At the latest meeting in the series, the issue was now the quantum structure of space–time itself.

Rare gases provide unique opportunities to examine patients and materials with magnetic resonance imaging. A new entry, krypton, offers interesting properties that could move the field forward.

With continuing improvements in X-ray optics, conventional techniques for measuring their performance are finding it hard to keep up. Iterative phase-retrieval algorithms for reconstructing an optical field at the focus of an optical element could not only solve this problem, but remove the need for such optics altogether.

Statistical physics can reveal the fabric of complex networks, for example, potential oligarchies formed by its best-connected members. But care has to be taken to avoid jumping to conclusions.

The tracking of the circulation of dollar bills around the United States, to map human travel patterns, has at last uncovered a physical example of a particular style of random walk.

Certain aspects of two-dimensional turbulence are remarkably similar to those found in critical percolation, and show conformal invariance. But there is both less, and more, to this observation than meets the eye.

The coalescence of neutron stars in compact binaries could produce the intense, short flashes of high-energy radiation observed in gamma-ray bursts. Models suggest that dynamical evolution in old dense stellar clusters, rather than galaxies, may form many of these rare systems.

Treating cancer with beams of high-energy protons is just one of the exciting possibilities presented by the advent of laser-based particle accelerators. But how soon will these devices reach the performance levels needed for such applications, and how will these improvements be made?

Depending on the temperature, the flow of current between two reservoirs of superfluid ⁴He exhibits phase slippage — a mechanism that creates vortices and leads to energy dissipation — or Josephson oscillations when the apertures connecting the reservoirs behave as a weak link.

The role of phonons in conventional superconductivity — first determined by isotope substitution — has been known for over half a century. But identifying the mechanism in unconventional superconductivity is a much more challenging affair.

The observation of macroscopic quantum coherent behaviour by a single polymer chain provides an important model system for studying the physics of reduced dimensionality, unperturbed by the disorder that can complicate the study of conventional inorganic systems.

The melting temperatures of the base-pair sequences in DNA are difficult to predict. But applying statistical physics to the problem has created an 'index' that well represents the molecule's thermal properties.

The ability to measure small or slow rotations relative to an inertial frame is valuable in navigation as well as in fundamental physics. A device that exploits techniques developed in atomic physics could lead to sensitive and compact rotation sensors.