Hard disk drive is the Primary storage device in our computer systems. A hard disk drive is a data storage device that uses magnetic storage to store and retrieve digital information. Most people now buy laptops for their computing needs and have to make the decision between getting either a Solid State Drive (SSD) or Hard Disk Drive (HDD) as the storage component. The primary characteristics of an HDD are its capacity and performance. Capacity is specified in unit prefixes corresponding to powers of 1000. 1 terabyte drive has a capacity of 1,000 gigabytes. Performance is specified by the time required to move the heads to a track or cylinder plus the time it takes for the desired sector to move under the head, and finally the speed at which the data is transmitted.
There have been a series of technologies developed to allow hard drives to increase in capacity with little effect on cost; one of the latest is perpendicular recording. The limitation of perpendicular recording is often characterised by the competing requirements of readability, writeability and stability commonly known as the Magnetic Recording Trilemma. HAMR is one technique proposed to break the trilemma and produce a workable solution.
Heat-assisted magnetic recording (HAMR) is a magnetic storage technology for hard drives in which a small laser is used to heat the part of the disk that is being written to. Heat-assisted magnetic recording (HAMR) is a hybrid of magnetic and optical technology that represents the latest innovation in HDD development.
Heat Assisted Magnetic Recording (HAMR) improves the writability of the media by focusing heat energy to assist grain reversal. This approach appears viable for use with planar perpendicular media, even though it requires significantly different materials than the cobalt-based alloys used today with FePt and CoPt alloys the leading candidates. The function of HAMR is basically to “trick” the head into magnetically switching a material by very rapidly heating the media directly in front of the head during the writing process. As the media cools, the head field is then strong enough to switch a small area of the media into an up or down orientation thereby creating a bit of stored information.