EPFL team uses perovskites to show how magneto-optical drives could be cheaper and faster than HDDs

Physicists at the École polytechnique fédérale de Lausanne (EPFL) in Switzerland have used perovskite materials to alter a magnetic bit's polarity with light, potentially opening the door to denser and faster disk drives using magneto-optical technology.

Researchers László Forró, Bálint Náfrádi, Péter Szirmai and Endre Horváth suggest magneto-optical drives using this method could be physically smaller, faster and cheaper than today's disk drives. They also say it is an alternative to heat-assisted magnetic recording (HAMR).

The researchers are now seeking investors to back a patent application and industrial partners to productize the proof of concept demonstration.

The EPFL team used visible light waves to write and re-write magnetic bits at room temperature. Previously it had only been possible by cooling a magnet to '180 degrees Celsius.

The researchers used a halide perovskite/oxide perovskite heterostructure, and the abstract of their scientific paper states 'demonstrate that photo-induced charge carriers from the CH₃NH₃PbI₃ photovoltaic perovskite efficiently dope the thin La_0.7SR_0.3MnO₃ film and decrease the magnetization of the ferromagnetic state, allowing rapid rewriting of the magnetic bit.'

The Swiss researchers placed a thin film of perovskite material on top of a magnetic substrate. Their paper states: 'We use a sandwich of a highly light sensitive (MAPbI₃) and a ferromagnetic material (LSMO), where illumination of MAPbI₃ drives charge carriers into LSMO and decreases its magnetism.'

MAPbI₃ is Methylammonium lead bromide and LSMO is Lanthanum strontium manganite; both are perovskites.