A recent study published in Acta Materialia showcased a breakthrough in hard disk drive (HDD) technology. Collaborating researchers from Seagate, NIMS, and Tohoku University introduced a novel approach called two-layer heat-assisted magnetic recording (HAMR). This innovative method has the potential to achieve an areal density of up to 4Tbpsi (terabits per square inch), significantly surpassing current HDD capabilities.
While existing HAMR-based products by Seagate can record at 1.5Tbpsi, enabling HDDs with capacities exceeding 30TB, the new dual-layer recording technique opens the door to even higher storage capacities. By extrapolating the potential of this technology, future HDDs could offer storage capacities exceeding 120TB, a substantial leap in data storage capabilities.
Various technologies have explored the concept of recording information on multiple layers. Optical discs with multiple recording layers and 3D flash memory with NAND flash cells on numerous layers have been previously demonstrated. However, the practical implementation of multiple-layer magnetic recording has remained elusive until now.
The research team's dual-layer magnetic recording demonstration utilized a specialized FePt-C granular perpendicular magnetic recording media. By employing a laser to heat the two magnetic layers to specific temperatures, data could be written on both layers, effectively doubling the storage capacity within the same physical space.
This dual-layer recording introduces four levels of magnetic states, allowing for higher density recording and increased data storage efficiency. While the full potential of four-level recording is still being explored, the initial results are promising for enhancing HDD magnetic recording density.
Although the integration of multi-layer perpendicular recording into commercial products may take a few years, the advancements made by Seagate, NIMS, and Tohoku University represent a significant step forward in HDD technology. This breakthrough could sustain the cost advantage of HDDs over NAND flash memory for the foreseeable future.
