Two reports 3:
Scientists create a version from the
natural magnet
Most materials Show some form of magnetic when placed in a magnetic field. As small compass needle, the electrons will follow the direction of the field. In the case of a ferromagnet, or permanent magnet, the compass needle remains linked even after the magnetic field is turned off.
Most of the products used magnet-speakers, electronic motor-ferrous, cobalt, nickel, or their alloys. But naturally limited list of the factors limiting the application, so researchers are turning to synthetic magnet.
From molecules to magnets
to try to coax from copper and manganese calculated out, the scientists turned to a carbon molecules called buckyballs quirky one. Buckyballs are molecules shaped soccer ball entirely of carbon atoms, and they have been helpful in this case because the electron affinity of them-they pull electrons off an adjacent metal.
To create magnet, researchers sent a thin layer of buckyballs, followed by a thin layer of copper or manganese, in a non-magnetic chip. Stacks are only 20 nanometers results thick, and researchers have demonstrated that it retains links from even after it has been taken out from school. Magnetization is weak-not nearly strong enough to stick to your organization-but its refrigerators represents the first demonstration of ferromagnetism in copper and manganese at room temperature. The results were published in nature.
Stacked Surface
Next the researchers have examined how, exactly, the materials generated from their schools. The high stack alternating layers of metal and magnetic buckyballs higher, implying that the word originated at the interface between the layers.
To verify this from so-called computer interfaces, the researchers moved into a unique technique known as muon spin rotation. By burying muon-subatomic particles also have a spin-like compass in different depths in multilayer stacks, and see the muon spin reorient itself, they can measure power from local areas attacks.
Muon at the interface metal / buckyballs have experienced the strongest rotations, indicating that it is the electrons are generated magnetic.
The path in the future
from structural properties of metal / buckyball is about 30 times weaker than iron. But Oscar Cespedes authors think that there is room for improvement. "Copper is pretty much as far away from as you can get," he said. That means that the mash-up multiple materials should exhibit effective. "We need to find a combination of the molecules and the metal to maximize efficiency."
At present, many users of industrial and technology magnet require rare earth elements, such as neodymium. We mainly mined in China, and as a result, are becoming increasingly expensive. Permanent magnets are made from materials readily available as copper and carbon may pave the way for the eco-friendly technologies, reducing our dependence on foreign minerals.
Also, because buckyballs are biocompatible, and may be done in a laboratory-based organic chemistry magnetism are hot research area right now. Copper / buckyball magnets can be used for medical applications, for example in MRI scans, without toxicity associated with today's MRI contrast agent
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