Scientists can alter a new material’s magnetism by varying its temperature
DENVER — A small change in temperature can alter a new material’s magnetic properties. It’s a unique feature. “No magnetic material known to man is known to do this,” reports Ivan Schuller. The physicist works at the University of California, San Diego. He described his team’s discovery here on March 3, at a meeting of the American Physical Society.
Schuller envisions this material as the basis of a new generation of hard drives. They would store data to be used by computers. Such a new device would apply small magnetic fields to write data. Then, when not in use, the device would change its temperature. This would raise the magnetic field strength needed to write new data — or alter its store of existing of data. With such a device, it would be hard to accidentally overwrite information (essentially erasing older data).
Schuller’s creation consists of nickel layered atop a compound made from vanadium oxide. Researchers already knew this oxide conducts an electrical current at high temperatures. At low temps, however, this oxide is an electrical insulator. That means it would block a current’s flow. Adding nickel created a hybrid material. And its magnetism — which is related to its electrical properties — suddenly became linked to temperature.
Schuller and his team showed they could alter the new material’s magnetic properties by adjusting its temp over a range of 20 degrees Celsius (36 degrees Fahrenheit). It’s the second new and unusual temperature-related effect identified in a vanadium oxide.
A device made from this new material could make data storage more robust and secure, Schuller predicts.
data Facts and statistics collected together for analysis but not necessarily organized in a way that give them meaning. For digital information (the type stored by computers), those data typically are numbers stored in a binary code, portrayed as strings of zeros and ones.
electric current A flow of charge, called electricity, usually from the movement of negatively charged particles, called electrons.
hard drive A device that reads and writes digital data — and hence can store data — onto a rigid magnetic disk.
insulator A substance or device that does not readily conduct electricity.
magnetic field An area of influence created by certain materials, called magnets, or by the movement of electric charges.
nickel A hard, silvery element (number 28 on the periodic table of elements). It resists oxidation and corrosion, making it a good coating for many other elements or for use in multi-metal alloys.
oxide A compound made by combining one or more elements with oxygen. Rust is an oxide; so it water.
physicist A scientist who studies the nature and properties of matter and energy.
vanadium A soft metallic element (number 23 on the periodic table of elements) that is structurally strong.