The material developed by Deepak K. Singh, associate professor of physics and astronomy and his team is created by depositing a magnetic alloy, or permalloy, on the honeycomb structured template of a silicon surface.
The magnetic diode paves the way for new magnetic transistors and amplifiers that dissipate very little power, thus increasing the efficiency of the power source. This could mean that designers could increase the life of batteries by more than a hundred-fold and less dissipative power in computer processors could also reduce the heat generated in laptop or desktop computers they say.
"Semiconductor diodes and amplifiers, which often are made of silicon or germanium, are key elements in modern electronic devices," said Singh, who also serves as the principal investigator of the Magnetism and Superconductivity Research Laboratory at MU. "A diode normally conducts current and voltage through the device along only one biasing direction, but when the voltage is reversed, the current stops. This switching process costs significant energy due to dissipation, or the depletion of the power source, affecting battery life. By substituting the semiconductor with a magnetic system, we believed we could create an energetically effective device that consumes much less power with enhanced functionalities."
THe diode was made of an ultrasmall permalloy magnet with a typical length of 12 nm and thickness of 6nm showed a unidirectional electron transport of 10 to 15 µA at room temperature. Importantly, the unidirectional biasing arises without the application of a magnetic field with an output power of around 30 nW that is 1000 times smaller than a semiconductor junction diode. Together, these properties provide new opportunities for spintronics research say the researchers.