Category Technology/Electronics

Highly nonlinear, fast and repeatable threshold switching behaviours of diffusive memristors.

A new type of nanodevice for computer microprocessors that can mimic the functioning of a neural synapse has been developed by Engineers at the University of Massachusetts Amherst. Such neuromorphic computing in which microprocessors are configured more like human brains is one of the most promising transformative computing technologies currently under study. Prof. Yang describes the research as part of collaborative work on a new type of memristive device.

Memristive devices are electrical resistance switches that can alter their resistance based on the history of applied voltage and current...

A cross-section of a perovskite solar cell seen through a scanning electron microscope. Credit: M.Grätzel/EPFL

EPFL scientists have stabilized perovskite solar cells by integrating rubidium into them. The innovation pushes power-conversion efficiency to 21.6%, ushering a new generation of perovskite solar cells. Perovskite solar cells have great potential for providing us with cost-effective solar energy. However, heat stability is an issue, and can significantly limit the solar cell’s long-term efficiency, as the cell’s structure can degenerate over time. A solution has been to mix perovskites with other materials, such as cesium, that can improve the cell’s stability without compromising its efficiency in converting light into electrical current.

Michael Grätzel’s lab at EPFL has now in...

Example of a hologram made using a new method based on optical forces. Credit: Montelongo et al. Nature Communications

Researchers have used the pressure of light, aka optical forces or “tractor beams”, to create a new type of rewritable, dynamic 3D holographic material. Unlike other 3D holographic materials, the new material can be rapidly written and erased many times, and can also store information without using any external energy. The new material has potential applications in 3D holographic displays, large-scale volumetric data storage devices, biosensors, tunable lasers, optical lenses, and metamaterials.

Recently the researchers demonstrated the reversible optical manipulation of nanostructured materials, which they used to fabricate active 3D holograms, lenses, and memory devices...

Schematic illustration and chemical structure of semi-printed plastic solar cells in air, using food additive o-MA as solvent. Credit: Long Ye, NC State

Researchers have created an efficient, semi-printed plastic solar cell without environmentally hazardous halogen solvents. These solar cells can be manufactured at room temperature, which has implications for large-scale commercial production. Plastic solar cells, or organic photovoltaics, are popular because they are lightweight, flexible, transparent and inexpensive to manufacture, making them useful in multiple applications. Unfortunately, the halogen-containing solvents used in their manufacture are an obstacle to large-scale commercialization...