Solid state drives are far faster than magnetic hard drives, and those spinning platters may not have a capacity advantage forever. Experts seem to agree that the current perpendicular recording technique for hard drives won't last past a theoretical maximum density of one terabit per square inch, and recent 3TB and 4TB drives are already consuming 625 gigabits per square inch, so there's not a whole lot of room to grow there. There are two favored techniques for expanding beyond that capacity, though, and one of them just got a shot in the arm: hard drive manufacturer Seagate says it's demonstrated a full 1Tb / in² areal density using heat-assisted magnetic recording (HAMR) technology. Basically, Seagate uses a laser to heat a microscopic portion of the disc so that more data can be written than the regular temperature would allow, a technique which the company says could quickly yield 6TB 3.5-inch hard drives, and 2TB 2.5-inch ones, before growing to theoretical capacities of up to 60TB for a drive assuming a 10Tb / in² yield.

That may sound pretty neat, but it's not exactly a record demonstration, as the competing bit-patterned media (BPM) technique has shown: by lithographically printing magnetic cells (rather than the traditional hard drive's magnetic grains) onto a disc's surface, researchers at a university in Singapore managed to demonstrate a far greater areal density of 3.3Tbit / in² last year. We'll just have to see how quickly Seagate plans to put its HAMR plans in motion: "later this decade" is as soon as the company is willing to promise right now.