Category Physics

This is a closer look at the target of frozen solution that contains the building blocks for the solar cell material. Credit: E. Tomas Barraza

Delicate hybrid organic-inorganic crystals open new possibilities for light-based technologies. Materials scientists at Duke University have developed a method to create hybrid thin-film materials that would otherwise be difficult or impossible to make. The technique could be the gateway to new generations of solar cells, LEDs and photodetectors.

Perovskites are a class of materials that – with the right combination of elements – have a crystalline structure that makes them particularly well-suited for light-based applications...

Researchers at Los Alamos National Laboraotry are creating double-pane solar windows that generate electricity with greater efficiency and also create shading and insulation. It’s all made possible by a new window architecture which utilizes two different layers of low-cost quantum dots tuned to absorb different parts of the solar spectrum. The approach complements existing photovoltaic technology by adding high-efficiency sunlight collectors to existing solar panels or integrating them as semitransparent windows into a building’s architecture.

Using two types of “designer” quantum dots, researchers are creating double-pane solar windows that generate electricity with greater efficiency and create shading and insulation for good measure...

This flat metalens is the first single lens that can focus the entire visible spectrum of light — including white light — in the same spot and in high resolution. It uses arrays of titanium dioxide nanofins to equally focus wavelengths of light and eliminate chromatic aberration. Credit: Jared Sisler/Harvard SEAS

Metalenses—flat surfaces that use nanostructures to focus light—promise to revolutionize optics by replacing the bulky, curved lenses currently used in optical devices with a simple, flat surface. But, these metalenses have remained limited in the spectrum of light they can focus well. Now a team of researchers at the Harvard John A...

Figure 1. (a) Three-dimensional crystal structure of YbSi2, (b) view along the a-axis, and (c) along the c-axis. (© 2017 Kurosaki et al. Phys. Status Solidi RRL 2017, 1700372. doi: 10.1002/pssr.201700372)

Researchers create a thermoelectric material (ytterbium silicide) with a high power factor at room temperature. TE materials display the thermoelectric effect: apply heat on one side, and an electric current starts to flow. Conversely, run an external current through the device, and a temperature gradient forms; i.e., one side becomes hotter than the other. By interconverting heat and electricity, TE materials can be used as either power generators (given a heat source) or refrigerators (given a power supply).

The ideal TE material combines high electrical conductivity, allowing the curr...