[DigitalToday reporter Jinju Hong] A next-generation magnetic memory material that can record information using light rather than electric current has been developed. Researchers expect the technology to deliver data writing speeds up to 1,000 times faster than existing magnetic memory and reduce power consumption.

Japan's ITmedia reported on June 10 that a research team from the National Institutes for Quantum Science and Technology (QST), the University of Hyogo and the Japan Synchrotron Radiation Research Institute said it had developed, for the first time in the world, a new material that can change a magnetic memory's writing state using laser light pulses alone. The results were published in the international journal Applied Physics Letters.

Unlike conventional semiconductor memory, which stores charge, magnetic memory stores information using the direction of electron spins. It distinguishes 0 and 1 depending on the spin direction. Current magnetic memory changes spin direction by running an electric current, which generates heat and consumes power, and there were limits to improving writing speed.

To solve these problems, the researchers designed a new structure that can switch spin direction using light alone. The key is to use the optical switching phenomenon. Optical switching refers to the phenomenon in which the direction of electron spins can be reversed through laser irradiation alone.

Ferrimagnetic materials capable of optical switching were already known, but there were limits to practical memory applications. That was because low spin alignment made it difficult to clearly distinguish writing states. By contrast, the cobalt-iron-boron (CoFeB) alloy widely used in current magnetic memory has high stability but cannot perform optical switching.

The team chose to combine the strengths of the two materials. It designed an artificial ferrimagnet by stacking CoFeB, gadolinium and cobalt in a three-layer structure. It then conducted atomic-level structural analysis at the Japanese research facility NanoTerasu to find the optimal composition. As a result, it succeeded in confirming that electron spin directions repeatedly flip due to lasers even in the CoFeB alloy, an existing memory material. Researchers from NTT and Tokyo University of Science also participated in the study.

The researchers explained that the achievement does not stop at developing a new material. They said securing both optical switching and the high stability of existing magnetic memory materials showed the possibility of applying the approach to actual memory devices.

They said an important achievement is securing reproducibility that allows writing states to be stably distinguished. Even if optical switching is possible, it is difficult to use it as memory if spin direction does not remain consistent.

The team sees strong potential for use in AI and data centres. It said rising AI computing is rapidly increasing data throughput, and power consumption problems at data centres are growing, and that high-speed, low-power memory could be a key technology to address this.

The technology is also expected to be used in next-generation information processing systems that connect optical communications and electronic circuits. That is because it could help reduce bottlenecks between optical communications, which transmit data using light, and electronics-based computing.

The industry is paying attention to the study because it shows the possibility of changing the way information is stored, beyond improving memory performance. But challenges remain for commercialisation, including applying it to actual memory devices, verifying long-term stability and securing mass-production processes.

There is also an assessment that if future research continues successfully, it could become an important turning point for shifting from current-centred memory technology to light-based technology.