Japanese electronics giant Sony Corporation has announced a new magnetic tape technology with a storage capacity of 185 terabytes (TB) on a single cartridge.

The areal density of 148 Gbit/in2 (gigabits per square inch) is said to be 74 times the capacity of current mainstream coated magnetic tape storage media. It allows more than 185 TB to be stored in a standard LTO Ultrium format data cartridge. The new tape has the world's highest areal recording density for magnetic tape storage.

Areal density is a measure used to quantify and compare different types of media used in data storage devices such as hard disk drives, optical disc drives and tape drives. The unit of measure is typically gigabits per square inch.

Sony said it achieved this feat by creating a nano-grained magnetic layer with fine magnetic particles and uniform crystalline orientation through the use of sputter deposition, a technique usd to form thin films consisting of multiple layers of crystals.

By "optimizing sputter conditions" and creating a smooth soft magnetic underlayer, Sony's primary data layer has fine magnetic particles 7.7 nanometers in size, on average.

Standard coated magnetic tape drives use simpler technology, but have significantly lower capacities with areal densities around 2 Gb per square inch. Sony's new magnetic tape technology features an areal density of 148 Gb per inch, which is 74 times denser.

Magnetic tape drives such as Sony's 185 TB are ideal for supercomputers and data centers that require large capacity storage without a huge physical footprint. As they're typically a slow form of storage, they aren't used in desktop PCs.

Sony said it will now work to commercialize the technology and developing advanced thin layer deposition technologies to further increase areal densities.