TDK strives for 1Tb/in² data density with new recording technology

The development department of the Japanese technology company TDK has succeeded in storing data on a magnetic storage medium and reading it back using a combination of a magnetic and optical read head.

During the Ceatec Japan 2009 technology fair, TDK will demonstrate its latest development in the field of data storage. The company says it can increase the data density of magnetic media to 1Tb/in², or about 155Gb per square centimeter, by supporting the magnetic read and write head with lasers. The technique was successfully applied for the first time on a platter with a rotational speed of 7200 revolutions per minute. reports Company.

To achieve the high data density, TDK had to use material that requires a strong magnetic field for demagnetization, a property called coercive field strength and expressed in Oersted. This way, data cannot be accidentally erased due to heat development. However, this material has the disadvantage that the magnetic fields must be very strong to write data: TDK uses a laser to heat the magnetic substrate very locally and thus reduce the required field strength.

The technology allows the use of magnetic perpendicular storage substrates with a coercive field strength of 16kOe instead of the usual 5kOE. TDK expects to be able to apply the technology in hard drives from 2011 or early 2012. The size of the area heated by the laser must then be reduced from a diameter of 75nm to 50nm in order to be able to dissipate the generated heat.