Viewpoints

A Breakthrough for Remote Lasing in Air

A Breakthrough for Remote Lasing in Air

December 17, 2014

Günter Steinmeyer

A scheme using two pump wavelengths in the infrared and ultraviolet produces more efficient laserlike emission in air, which could benefit remote sensing applications.

X-Ray Line May Have Dark Matter Origin

X-Ray Line May Have Dark Matter Origin

December 15, 2014

Kevork N. Abazajian

An x-ray feature recently detected by different astronomy groups may be the long-awaited signature of dark matter.

Power to the Electrons

Power to the Electrons

December 8, 2014

Georg Korn

A laser-driven particle accelerator, delivering a beam of electrons with a record-breaking energy of 4.2 giga-electron-volts, could lead to compact x-ray lasers or high-energy colliders.

Spin Transport Goes Ballistic

Spin Transport Goes Ballistic

December 4, 2014

Henri Jaffrès

The injection of spins into a high-mobility two-dimensional electron gas is unexpectedly efficient, suggesting that new theories may be needed to describe spin transport in such systems.

Synopses

Work in the Quantum World

Work in the Quantum World

December 18, 2014

A new method of measuring work in a quantum-mechanical setting provides a way to evaluate the thermodynamics of small, fluctuating systems.

How Oxygen Kindles Fireflies

How Oxygen Kindles Fireflies

December 17, 2014

X-ray images of the light-emitting organs in fireflies clarify the mechanism by which oxygen controls the insects’ luminescence.

Searching for Millicharged Particles

Searching for Millicharged Particles

December 16, 2014

Tiny dielectric spheres in an optical trap are used to search for hypothetical particles with a small fractional charge.

Cosmic Ruler Measured More Directly

Cosmic Ruler Measured More Directly

December 11, 2014

A measure of how galaxies are spatially distributed can be determined in a new, more robust way.

Focus

Heavily Interconnected Economies Are Vulnerable to Shocks

Heavily Interconnected Economies Are Vulnerable to Shocks

December 19, 2014

A network analysis finds that the European economies with the most interconnections, like Germany, are the most vulnerable to economic crises in the absence of government intervention.

Nanopyramids’ Color Depends on Viewing Direction

Nanopyramids’ Color Depends on Viewing Direction

December 12, 2014

An array of nanometer-sized aluminum pyramids acts as a directional antenna for light, and the direction depends on wavelength.

Notes from the Editors

X-Ray Lasers, Big and Small

X-Ray Lasers, Big and Small

December 10, 2014

A visit to SLAC and Lawrence Berkeley Lab offers a look at two complementary approaches to making the x-ray source of the future.


Keep Up With Physics

twitter icon feed icon mail icon

American Physical Society Sites


APS Home

Journals

PhysicsCentral

Physics Frontline