Category Physics

A schematic of the new laser system. Credit: Image courtesy of Northwestern University

High power and rapid tuning for the detection of hazardous chemicals. From their use in telecommunication to detecting hazardous chemicals, lasers play a major role in our everyday lives. They keep us connected, keep us safe, and allow us to explore the dark corners of the universe. Now a Northwestern University team has made this ever-important tool even simpler and more versatile by integrating a mid-infrared tunable laser with an on-chip amplifier. This breakthrough allows adjustable wavelength output, modulators, and amplifiers to be held inside a single package.

With this architecture, the laser has demonstrated an order-of-magnitude more output power than its predecessors, and the tuning range has ...

GaInP/SHJ tandem solar PV cells with efficiency up to 29.8% under 1-sun standard illumination

NREL and CSEM scientists have jointly set a new world record for converting non-concentrated (1-sun) sunlight into electricity using a dual-junction III-V/Si solar cell. The newly conversion efficiency of 29.8% was set using a top cell made of gallium indium phosphide developed by NREL, and a bottom cell made of crystalline silicon developed by CSEM using silicon heterojunction technology. The two cells were made separately and then stacked by NREL.

“It’s a record within this mechanically stacked category,” said David Young, a senior researcher at NREL. “The performance of the dual-junction device exceeded the theoretical limit of 29.4% for crystalline silicon solar cells.”
“We believe that the si...

This is an artist’s rendering of P22-Hyd, a new biomaterial created by encapsulating a hydrogen-producing enzyme within a virus shell. Credit: Indiana University

Combining bacterial genes, virus shell creates a highly efficient, renewable material used in generating power from water. A modified enzyme that gains strength from being protected within the protein shell, “capsid” – of a bacterial virus, this new material is 150X more efficient than the unaltered form of the enzyme.

“Essentially, we’ve taken a virus’s ability to self-assemble myriad genetic building blocks and incorporated a very fragile and sensitive enzyme with the remarkable property of taking in protons and spitting out hydrogen gas,” said Prof. Trevor Douglas...

Sandia National Laboratories technician Eric Breden installs a transmission cable on the silver disk that is the new pulsed-power machine’s central powerflow assembly. Credit: Randy Montoya

A new Sandia National Laboratories accelerator called Thor is expected to be 40X more efficient than Sandia’s Z machine, the world’s largest and most powerful pulsed-power accelerator, in generating pressures to study materials under extreme conditions.”Thor’s magnetic field will reach about one million atmospheres, about the pressures at Earth’s core,” said David Reisman, lead theoretical physicist.

Though unable to match Z’s 5 million atmospheres, the completed Thor will be smaller—2,000 rather than 10,000 square feet—and will be considerably more efficient due to design improvements that use hundre...