Multiferroic Magnetic Materials can Increase Power Efficiency of Computers

Researchers at University of California, Los Angeles, have used a new class of materials called "multiferroics"to reduce energy consumed by logic devices. Multiferroics can increase power efficiency for processing by nearly 1,000 times.

 The research could help design computers and other electronic devices that are faster and more energy efficient than the current systems.

The study was conducted by researchers at UCLA Henry Samueli School of Engineering and Applied Science and colleagues.

Laptops and smartphones get heated after prolonged use due to the energy that's being wasted by the microprocessor.

Currently microprocessors use electric current. Transistors in these microprocessors act as tiny "electronic switches," and regulate movement of electrons. As electricity passes through circuits, it meets resistance, which in turn produces heat and warms the device.

Also, these switches can "leak" electrons, meaning that they can never be completely shut down.

Researchers have used now multiferroic magnetic materials to reduce energy consumption of logic gates, which are circuits designed to perform calculations.

Multiferroic magnetic materials are new class of materials that are both electrically charged (ferroelectric) and magnetic (ferromagnetic). Their magnetization is controlled by electricity. Several research groups have been trying to use these unique materials to develop memory devices and logic gates. Ferroelectric materials  exhibit spontaneous electric polarization.

According to UCLA researchers, alternating voltage can switch on or off a multiferroic. It then carries the power through the material via spins of electrons. The process is known as spin wave bus.

Principal investigator Kang L. Wang described spin wave as an ocean wave where the water molecules are in the same place but the energy cascades through the water. Electric current can be thought of water flowing in a pipe.

"Spin waves open an opportunity to realize fundamentally new ways of computing while solving some of the key challenges faced by scaling of conventional semiconductor technology, potentially creating a new paradigm of spin-based electronics," Wang said in a news release.

Researchers were able to show that multiferroic materials can increase power efficiency for processing by 1000 times.

"Electrical control of magnetism without involving charge currents is a fast-growing area of interest in magnetics research," said Pedram Khalili, a UCLA assistant adjunct professor of electrical engineering, co-author of the study. "It can have major implications for future information processing and data-storage devices, and our recent results are exciting in that context."

The study is published in the journal Applied Physics Letters.

The study was funded by the Defense Advanced Research Projects Agency's Non-Volatile Logic program and the by the Nanoelectronics Research Initiative through WIN.

Watch Gregory Carman of UCLA's mechanical and aerospace engineering department explain about ongoing multiferroic research and its applications in a YouTube video (below), which was posted in 2013.