Category Technology/Electronics

Scientists explain how the giant Magnetoelectric Effect occurs in Bismuth Ferrite

The spin cycloid structure in BiFeO3. Credit: MIPT press-office

The spin cycloid structure in BiFeO3. Credit: MIPT press-office

Electromagnetic effect allows to control magnetic ‪polarization of a material by applying external electric field. Materials with such properties may be used to develop a new generation of ultra-energy efficient‪ computer memoy . A team proposed a theoretical model that explains the unexpectedly high values of the linear magnetoelectric effect in BiFeO3 (bismuth ferrite) that have been observed in a number of experiments and also suggested a way of further enhancing the effect.

One particular feature of bismuth ferrite is that in bulk samples, spins of Fe3+ iron ions are arranged in the form of a cycloid. This spin structure can be destroyed by a strong magnetic field or mechanical stress...

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Switch and Stick: Potential new Adhesive can be Turned On and Off

Glued to the spot: Max Planck scientists from Stuttgart have used gallium as an adhesive to grip a glass sphere with a movable punch model. The metal is located at the bottom of the punch model. Once it touches the glass sphere, the researchers heat the gallium and then cool it off again, so that it connects to the glass. This way, they can retract the sphere from the surface. Credit: © MPI for Intelligent Systems

Glued to the spot: Max Planck scientists from Stuttgart have used gallium as an adhesive to grip a glass sphere with a movable punch model. The metal is located at the bottom of the punch model. Once it touches the glass sphere, the researchers heat the gallium and then cool it off again, so that it connects to the glass. This way, they can retract the sphere from the surface. Credit: © MPI for Intelligent Systems

Researchers are suggesting gallium as just such a reversible adhesive. By inducing slight changes in temperature, they can control whether a layer of gallium sticks or not. This is based on the fact that gallium transitions from a solid state to a liquid state at ~30C...

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Mille-feuille filter removes Viruses from Water

The sheet made of cellulose nanofibers in the mille-feuille filter which can remove resistant viruses from water. Research led by Albert Mihranyan, Professor of Nanotechnology at Uppsala University, Image by Simon Gustafsson. Credit: Simon Gustafsson

The sheet made of cellulose nanofibers in the mille-feuille filter which can remove resistant viruses from water. Research led by Albert Mihranyan, Professor of Nanotechnology at Uppsala University, Image by Simon Gustafsson. Credit: Simon Gustafsson

A simple paper sheet made by scientists at Uppsala University can improve the quality of life for millions of people by removing resistant viruses from water. The sheet, made of cellulose nanofibers, is called the mille-feuille filter as it has a unique layered internal architecture resembling that of the French puff pastry mille-feuille (English translation thousand leaves)...

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High-Efficiency Power Amplifier could bring 5G Cell Phones

This diagram shows the standard layout of transistors in cell phone power amplifiers, at left, and a new highly efficient amplifier design, at right. The new design could help make possible next-generation cell phones, low-cost collision-avoidance radar for cars and lightweight microsatellites for communications. Credit: Image courtesy of Purdue University

This diagram shows the standard layout of transistors in cell phone power amplifiers, at left, and a new highly efficient amplifier design, at right. The new design could help make possible next-generation cell phones, low-cost collision-avoidance radar for cars and lightweight microsatellites for communications. Credit: Image courtesy of Purdue University

A new highly efficient power amplifier for electronics could help make possible next-generation cell phones, low-cost collision-avoidance radar for cars and lightweight microsatellites for communications. 5G mobile devices expected around 2019 will require improved power amplifiers operating at very high frequencies...

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