Science / Research

A voltage just taught graphene to switch its magnetism on and off

Cornell researchers have shown that applying a voltage to four layers of graphene slides the layers into a new pattern, flipping the material between nonmagnetic and magnetic states that stay put when the power is removed.

Ithaca, New York · October 18, 2026

Magnetism is usually something a material either has or does not. A Cornell team led by Kenji Yasuda has shown it can be a setting instead. Working with tetralayer graphene, four stacked sheets of carbon each one atom thick, the researchers applied a voltage that physically slides the layers against each other. In one arrangement, called Bernal stacking, the material is nonmagnetic. Slid into the other, rhombohedral stacking, it turns magnetic. The study, with Daniel Brandon as lead author, was published in Nature Nanotechnology on October 14.

The detail that lifts this above a laboratory curiosity is that the switch is nonvolatile. The magnetic state persists after the voltage is removed, rather than vanishing the moment the power stops. That is the property memory technology is built on: a state that holds without a constant supply of energy, and that can be rewritten on demand. Here the rewriting is structural. The voltage does not just nudge electrons around, it rearranges the material itself, and the magnetism follows the arrangement.

Keep the claim at the size the researchers themselves make it. Yasuda's team frames the result as a path toward reconfigurable quantum materials and new forms of nonvolatile memory, and that framing is honest about the distance involved. A four layer flake in a Cornell lab is a long way from a chip. What the work actually proves is narrower and more valuable: that layer position in these stacked materials can act as a clean, reversible control, electrical in and magnetic out, with no power needed to hold the result.

That is why physicists pay attention to stacking. Two dimensional materials earn their strange properties from how their sheets sit on one another, and most ways of changing that arrangement are slow, mechanical or one way. A voltage is none of those. If sliding layers can be made to work reliably at scale, the same trick could become a general tool for switching properties that are currently fixed at the factory. For now it is a demonstration, carefully done and independently listed, and it is a genuinely elegant one.