In a groundbreaking experiment, scientists have discovered that ultrafast laser pulses can significantly speed up how data is stored in magnetic devices, potentially leading to more energy-efficient data storage.
Rahul Jangid, a Ph.D. student at UC Davis, spearheaded this exciting research.
To grasp this discovery, let’s dive into some basics. Magnetic materials have regions called ‘domains,’ which are like tiny magnets with north and south poles.
In data storage devices like hard drives, these domains are used to represent data.
Jangid and his team wanted to understand what happens when these domains are hit with very short bursts of laser light.
The team found something astonishing: when a magnet is zapped with a pulsed laser, the domain walls (the boundaries between these magnetic regions) move at about 66 kilometers per second.
This speed is nearly 100 times faster than what scientists previously thought possible.
This finding is surprising because of something known as the Walker breakdown phenomenon, which suggests there’s a speed limit to how fast domain walls can move.
But this research shows that with lasers, these walls can move much faster than previously believed.
In many of our devices, like laptops and cell phones, we use flash drives for storage. But large data centers, which store vast amounts of information, still rely on hard disk drives.
These drives use a lot of energy, especially when flipping bits of data.
The exciting part of this research is that using laser pulses instead could mean these flips use much less energy.
With projections indicating that information and communications technology could account for 21% of the world’s energy demand by 2030, finding energy-efficient solutions is critical.
This discovery comes at a crucial time in our quest for sustainable technologies.
The experiment was conducted at the FERMI facility in Italy, using a free electron laser—a massive, 2-mile-long vacuum tube. Here, electrons are sped up to near light speed, creating incredibly bright X-rays.
The team used these X-rays to observe a nano-scale magnet, made of layers of cobalt, iron, and nickel, when hit by femtosecond laser pulses (a femtosecond is unbelievably short—there are more femtoseconds in a second than days in the universe’s age).
While the technology is not yet ready for everyday use—current lasers still consume a lot of power—the future possibilities are exciting. The idea is similar to how CDs use lasers for storing and playing back information.
Jangid, now continuing his research at the Brookhaven National Laboratory, is excited about further exploring this field. The next steps involve understanding the physics behind these ultrafast domain wall movements and imaging the process.
This research could lead to revolutionary changes in how we store and process data, making it faster and more energy-efficient. It’s a significant step towards low-power spintronics, a technology that could shape the future of data storage and information processing.
