At the Indian Institute of Science in Bangalore, researchers have discovered that electric current can do something far more profound than simply power a device — it can rewrite a material's magnetic identity entirely. By pushing a complex oxide material across a critical threshold, the team transformed it between fundamentally different magnetic states, each carrying a distinct electrical resistance. Published in Nature Communications, this work by Bhagwati Prasad and Suryakanta Mondal opens a quiet but consequential door toward memory and logic technologies built for the cold, precise world
IISc breakthrough uses electric current to switch magnetic states for quantum devices
The electric current doesn't rotate magnetization; it changes the magnetic phase itself.
Mark
Why does it matter that the current changes the magnetic phase itself, rather than just flipping the direction?
Mimi
Because it creates two completely different resistance states. When you just flip direction, you're working with the same underlying magnetic structure. Here, the material becomes something else entirely—the electrons rearrange. That gives you a much sharper, more reliable distinction between on and off.
Mark
And that's useful for memory because...
Mimi
Because memory needs to store information in stable, distinguishable states. Two resistance levels that are 200 percent apart are easy to read and hard to confuse. Plus, they're reversible—you can switch back and forth without degrading the material.
Mark
Why is this particularly suited to quantum computers?
Mimi
Quantum computers run at temperatures near absolute zero. Most new technologies struggle there. But this effect actually gets stronger as temperature drops. So instead of fighting the cold, the device thrives in it.
Mark
What's the catch?
Mimi
Right now it takes a lot of current to make the switch happen. And it only works well at cryogenic temperatures. If they can reduce the switching energy and expand the temperature range, it becomes practical. That's the next phase.
Mark
How close are they to that?
Mimi
They've proven the concept works. Now it's engineering—optimization. That's usually the harder part, but also the part where real applications emerge.
Le Pouls
- The race to build practical quantum computers has long been stalled by the absence of memory and logic devices that function reliably at cryogenic temperatures — IISc's discovery directly confronts that gap.
- Rather than merely flipping a magnetic direction like conventional technologies, the researchers found that electric current can collapse an entire magnetic phase and rebuild it as something structurally different, a far more dramatic transformation.
- Nanoscale tunnel devices just 250 by 250 nanometres demonstrated magnetoresistance exceeding 200%, with switching controlled by current, temperature, or magnetic field — proof that the effect is not just observable but engineerable.
- The phenomenon is strongest at the very low temperatures where quantum computers already operate, suggesting these devices could integrate into quantum platforms without requiring separate environmental conditions.
- The team is now working to reduce the energy cost of each switching event and broaden the temperature range, the two remaining barriers between laboratory demonstration and real-world deployment.
At the Indian Institute of Science in Bangalore, researchers have discovered that electric current can do something far more profound than simply power a device — it can rewrite a material's magnetic identity entirely. By pushing a complex oxide material across a critical threshold, the team transformed it between fundamentally different magnetic states, each carrying a distinct electrical resistance. Published in Nature Communications, this work by Bhagwati Prasad and Suryakanta Mondal opens a quiet but consequential door toward memory and logic technologies built for the cold, precise world of quantum computing.
At the Indian Institute of Science in Bangalore, a research team led by materials engineer Bhagwati Prasad and PhD student Suryakanta Mondal has demonstrated a new way to use electric current — not merely to power a device, but to fundamentally transform the magnetic character of a material. Their findings, published in Nature Communications, point toward compact, energy-efficient devices capable of supporting quantum computers.
Most magnetic memory technologies work by reversing the direction of a material's magnetism, much like flipping a compass needle. The IISc team pursued something more radical. They studied a complex oxide material capable of hosting multiple magnetic states and asked whether electric current could push it to change its magnetic nature entirely. At low current levels, the material remains ferromagnetic — its atomic moments aligned, its electrical resistance low. But beyond a critical threshold, it abruptly shifts into an antiferromagnetic-like state, where neighboring moments oppose one another and resistance rises sharply. The current isn't rotating the magnetization; it is rewriting the material's magnetic phase, causing electronic orbitals to rearrange themselves in the process.
To test practical utility, the team fabricated nanoscale tunnel devices roughly 250 by 250 nanometres — small enough for billions to fit on a single chip. These structures displayed two stable, distinguishable resistance states and achieved magnetoresistance exceeding 200 percent. Crucially, the effect proved strongest at very low temperatures, precisely the cryogenic conditions in which quantum computers already operate, suggesting seamless integration into future quantum platforms.
Significant work remains. The researchers are now focused on reducing the energy required to trigger each switch and on extending the device's functional temperature range. If successful, the result could be a new class of low-power devices that don't merely operate within quantum systems — but belong there.
At the Indian Institute of Science in Bangalore, a team of researchers has demonstrated something that could reshape how we build the next generation of computing devices. They've found a way to use electric current to fundamentally transform a material's magnetic identity—not just nudge it in a new direction, but completely flip it from one state to another. The work, published in Nature Communications and led by materials engineer Bhagwati Prasad alongside PhD student Suryakanta Mondal, suggests a path toward compact, energy-efficient devices that could one day support quantum computers.
Most magnetic memory technologies work by reversing the direction a material's magnetism points, like flipping a compass needle. The IISc team took a different approach. They studied a complex oxide material that naturally hosts multiple magnetic states, and they asked whether an electric current could push the material to switch not just its magnetic direction but its entire magnetic character. The answer turned out to be yes. At low current levels, the material sits in a ferromagnetic state—its atomic magnetic moments largely aligned in the same direction, allowing electricity to flow easily with minimal resistance. But as the current increased past a critical threshold, something dramatic happened. The material abruptly transformed into an antiferromagnetic-like state, where neighboring magnetic moments point in opposite directions. This new state has much higher electrical resistance.
What makes this transition fundamentally different from conventional magnetic switching is that the electric current isn't simply rotating the magnetization; it's rewriting the material's magnetic phase entirely. The long-range ferromagnetic order collapses, and the material's electronic orbitals rearrange themselves. This creates two clearly distinguishable resistance states—a property Prasad describes as potentially valuable for cryogenic memory and logic technologies. The transition is reversible, meaning the material can be switched back and forth reliably.
To test whether this effect could actually be useful, the researchers fabricated nanoscale tunnel devices measuring roughly 250 by 250 nanometres—structures small enough to fit billions on a single chip. These tiny devices displayed two stable resistance states and achieved magnetoresistance exceeding 200 percent, a substantial effect. The switching could be controlled by adjusting the electric current, the temperature, or an applied magnetic field. The effect proved strongest at very low temperatures, which is precisely where quantum computers operate. Most quantum systems require cryogenic conditions to function, so a memory or logic device that works best in that same cold environment could integrate seamlessly into future quantum platforms.
The discovery opens a practical pathway, but significant work remains. The researchers are now focused on reducing the amount of current and energy needed to trigger the switching, and on adapting the device to work across a wider range of temperatures. If they succeed, the result could be a new class of low-power electronic and quantum devices that operate more efficiently than what exists today. For now, the breakthrough demonstrates that electric current can do more than power a device—it can fundamentally reshape the material itself.
Citations marquantes
Our initial motivation was to understand whether the closely competing magnetic states could be controlled directly using an electrical current.— Suryakanta Mondal, PhD student and first author
What is fundamentally new is that the electric current does not merely rotate the magnetisation; it changes the magnetic phase of the material itself.— Bhagwati Prasad, Assistant Professor, Department of Materials Engineering
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