The gadget you’re using to view this article very definitely works by storing zeroes and ones in bits of semiconductor, specifically silicon powered by electricity.
That kind of energy utilization won’t cut it in the future where net-zero carbon emissions are the goal. Fortunately, researchers aim to fundamentally alter the way computers operate, leading to more robust, low-energy machines. One method is to construct a computer using magnets.
Researchers at the University of Michigan have developed a novel iron alloy in collaboration with chipmaker Intel that might be a key component of future magnet-based computers. Their findings were just published in Nature Communications.
Their alloy has a magnetostrictive effect. It is based on the notion that when a magnetic substance, such as iron, is immersed in a magnetic field, it gently changes form. You can build alloys that are more magnetostrictive or flexible when their magnetic fields vary by adding other metals (an alloy is a blend of metallic elements) and fine-tuning their proportions.
Today, magnetostrictors aid in developing high-quality sensors because we can detect changes in the form of a good magnetostrictor in the presence of magnetic fields, even if they are weak. You can shape-shift a magnetostrictor by employing electrical current to produce magnetic fields. You may transform the electrical energy of the current into the mechanical energy of the magnetostrictor changing form in this manner rather readily.
That is a significant skill. Magnetostrictors may one day allow us to create the zeroes and ones that constitute the unseen bedrock of all our computer systems using minuscule, changing magnetic fields.
Magnetostrictors, on the other hand, have gone out of favor in recent years. “The magnetostrictor has been pushed under the rug,” says John Heron, a materials scientist at University of Michigan, one of the paper’s authors.
There is, however, a reason to pay attention to them. Rare-earth metals like terbium and dysprosium are used in today’s finest magnetostrictors. Rare piles of the earth are (predictably) scarce and costly. The process of mining and extracting them is complex and sometimes results in harmful waste. With China controlling most production, the global rare-earth trade is sensitive to shifting geopolitics and trade disputes between the United States and China.
That’s why Heron and his colleagues decided to build a superior magnetostrictor by combining iron with gallium, a soft, silvery metal found only as trace components in aluminum and zinc ores. The melting point of pure gallium is so low that it will turn into liquid in your hands.
The University of Michigan researchers are far from the first to employ gallium to create magnetostrictive materials, but they had hit a snag.
“When you get past 20% gallium, the material becomes unstable,” Heron explains. “The symmetry of the material shifts, the crystal structure shifts, and the material’s characteristics shift dramatically.” For one thing, the material loses its shape-shifting magnetostrictive properties.
Heron and his colleagues had to block the atoms from modifying their structure to get around that constraint. As a result, they created their alloy at a relatively low temperature of 320 degrees Fahrenheit (160 degrees Celsius), restricting the energy of its atoms. Even as the researchers pumped extra gallium into the alloy, this kept the particles in place and prevented them from migrating about.
The researchers produced an iron alloy with up to 30% gallium using this approach, resulting in a novel material that is twice as magnetostrictive as rare-earth analogs.
This new, more efficient magnetostrictor might help scientists create a computer that is not only cheaper but also does not rely on rare-earth materials, whose extraction emits a lot of carbon.
In the extensive scope of things, the average home computer doesn’t consume a lot of power. The internet’s supercomputer data centers, on the other hand, are a different story. While the actual quantity of force used and carbon emissions produced by the centers is debatable, there is no doubt that they require a significant amount of energy.
Researchers like Heron seek to create technologies that completely modify how computers function to cut energy consumption. Magnetostrictors may be one method to do this. Tomorrow’s computers may employ magnetostrictors to work in bits of the magnetic field instead of semiconductors, which require constant power. Instead of requiring continuous power, such gadgets would only require electricity to turn a zero to a one or vice versa.
Aside from saving energy, such a computer would offer several benefits over its current equivalents. You wouldn’t lose what you were doing if it went off abruptly since the chunks of the magnetic field would remain in place. Engineers also believe that scaling up the specifications of these hypothetical computers will be easy, permitting performance levels that today’s semiconductors are unlikely to achieve.
However, because the technology is still in its early stages, it’s unclear when or even if we’ll see magnetostrictor-based gadgets in our homes. “In how many years do I see it becoming an iPhone technology?” Heron asks. “Well, maybe 20 or 30 if I’m lucky. “Perhaps never.”
He explains, “But showing the essential bit is something that we’re doing today.”