Conventional hard disks consume a lot of energy and are slow.

A technology has been developed to improve the speed of next-generation domain wall-based magnetic memory.

This research was developed by a research team led by Professor Gapjin Kim of the Korea Advanced Institute of Science and Technology and Professor Kyungjin Lee of Korea University, and was published in the September 25th issue of Nature Materials, a journal in the field of physics and materials science.

Conventional hard disks have the non-volatile characteristic of being able to retain information without an external power supply, but they had limitations such as high energy consumption and slow speed because they store information by rotating a disk.

Domain wall memory is a novel memory device characterized by non-volatile, low-power properties that operates through the movement of domain walls in magnetic nanowires rather than mechanical rotation. However, as the operating speed remains at several hundred m/s, the development of core technologies to increase the operating speed is required for practical application.

While most research on domain wall memory uses 'ferromagnetic' materials, the research team utilized the 'ferrimagnetic' GdFeCo and discovered a phenomenon where the movement speed of domain walls accelerates rapidly to several km/s under specific conditions.

In the case of ferromagnetic materials, the magnetization within the material is directed in one direction, making it impossible to avoid the Walker decay phenomenon, which is known as the cause of low speed.

However, in GdFeCo, the magnetization of Gd and FeCo is aligned antiparallel, so the Walker decay phenomenon disappears at the point where the sum of the two angular momentum is zero, and the velocity of the domain walls was successfully increased to more than 2 km/s at room temperature.

If ultra-high-speed operation characteristics are added to domain wall memory based on this research achievement, it is expected to become a next-generation memory with high integration, low power consumption, and non-volatility that surpasses hard disks.

Professor Kim Gap-jin stated, “This research is significant in that it discovered a new physical phenomenon that occurs at the point where the angular momentum of a ferrimagnetic material is zero, and it is expected to accelerate the realization of next-generation memory in the future.”