Researchers develop new HDD read head design

Researchers at the National Physical Laboratory in Teddington are developing innovative sensors to quickly read huge amounts of data on a hard disk.

The new sensors are designed to cope with the increasing amount of data being stored on hard drives, which has soared over the past 30 years to around 200 gigabits per square inch.

The new design could lead to thinner, and smaller read heads, capable of reading data on drives with data densities of one terabit per square inch.

The sensors would also use less power than current read heads, making them ideal for portable devices such as laptops. They could read back data ten times faster than is currently possible.

Current hard drives use the magneto-resistance effect to read data. This requires a constant current which converts resistance to voltage.

The new sensors use the magneto-electric effect. This allows data’s magnetic field to directly generate voltage instead of resistance.

The new heads will use seven layers of materials with different magnetic and electric properties, compared with current sensors which use 15 layers, and are significantly lighter. Researchers believe the new design could eventually lead to sensors thinner than 10 nanometers.

However assembling the complex alloys of the tiny sensors is proving challenging, as the materials used all have different properties - for example one material might be sensitive to oxygen, while another requires oxygen.

The new sensor design was published in the Journal of Applied Physics. The research team was led by Marian Vopsaroiu.