Category Physics

The entire solar material for the sample with less than or equal to 30 percent selenium is photoactive (top) while the bottom of the solar material for the image below contains greater than 35 percent selenium and has reduced photoactivity. Credit: ORNL

Solar cells based on cadmium and tellurium could move closer to theoretical levels of efficiency because of some sleuthing by researchers at the Dept of Energy’s Oak Ridge National Lab. A team used advanced microscopy to discover efficiency differences of crystalline structures of various mixtures of cadmium, tellurium and selenium. In fact, selenium is an integral part of the formulation that resulted in a world record for solar cell efficiency.

While some of today’s solar cells use a blend of cadmium and tellurium to convert light into el...

High-powered lasers melt mineral for planet formation experiments. Researchers observed the melting of forsterite, the most common constituent of Earth’s mantle, to understand how the cores of planets form and develop. The laser is able to create pressures representative of the extreme collisions between objects in space. The target is a 4 millimeter square. Al is aluminum and Qz is quartz. Image by Toshimori Sekine, Hiroshima University. Image may only be re-used with attribution. Credit: Image courtesy of Hiroshima University

New experiments provide insight into how Earth-type planets form when giant asteroids or planetesimals collide and how the interiors of such planets develop...

The Medium Scale High Voltage Test apparatus in TA-53 Building 10 allowed scientists to test electric fields in liquid helium, a crucial part of upcoming experiments into the nature of matter and antimatter. Credit: Image courtesy of Los Alamos National Laboratory

Why is so much more matter than antimatter present in the universe? A clue to this mystery may be provided by a sensitive search for a separation of positive and negative charges inside the neutron, which is referred to as the neutron’s “electric dipole moment” (EDM). The detection of a nonzero EDM in a particle such as the neutron would imply an asymmetry between matter and antimatter, which may explain the imbalance in the amounts of matter and antimatter now observed in the universe.

Scientists have been searching for evidence...

Scientists inserted helium ions into a thin crystalline film (gold) to controllably increase the out-of-plane crystal dimension, while the underlying substrate (black) fixed the in-plane directions. The red balloon represents one helium atom in the crystalline lattice. Credit: Oak Ridge National Laboratory

With just a bit of helium, the lighter-than-air element that makes balloons float, scientists have done what was once thought impossible – they stretched a crystal lattice in just one dimension, allowing them to tune the structure’s electronic and magnetic properties. To achieve this elongation, scientists devised a new method called “strain doping.” Scientists implant helium ions into a crystal. The helium gently pushes up against the structure, like a balloon under a sheet...