Thermal processes involved in heat-assisted magnetic recording paves the way for commercial devices

Nov 07, 2012
Applying heat during magnetic recording can improve storage densities far beyond their current levels. Credit: iStockphoto/Thinkstock

Most electronic data is stored on magnetic hard drives that spin at many thousands of revolutions per minute. To keep pace with ever-growing storage demand, however, achieving greater storage capacities by simply increasing the size of disks is infeasible. The required spinning speed would put immense physical strain on the components, particularly on the writing 'head'—a small needle-like object used to write data at particular points on the disk.

An alternative technology, heat-assisted (HAMR), is now a significant step closer to commercial realization, thanks to the efforts of Baoxi Xu and his co-workers at the A*STAR Data Storage Institute, Singapore. In a system using HAMR, is emitted from a diode on the write head to locally heat the disk during data writing. This technique has the potential to increase a standard disk's recording density by as much as two orders of magnitude. However, the additional heat can cause components such as the write head to destabilize and fall out of alignment.

By studying the of the head, the thermal effects on the disk and the thermal response of the lubricant in HAMR, Xu and his co-workers discovered how to maximize the recording density of the medium. They began by establishing the three major heat sources present in the device: the laser diode, the optical transducer, which concentrates the into a nanometer-sized spot, and the write pole, which performs the physical recording.

They found that the temperature of the transducer depends on both its size and distance from the write pole—both of which can be easily controlled in a commercial device. They also found that the in the HAMR head does not significantly inhibit the performance of the , which is important.

Xu and his team's results showed that the recording density of the medium can be maximized by reducing the number of layers through which the must pass before it can dissipate. This will be of prime importance for achieving the required high-density data storage goals of commercial devices. This study therefore represents an important breakthrough in our understanding of HAMR, and will be essential in bringing this technology closer to commercial fruition.

"Our work indicates the seriousness of the problems in the HAMR head, which gives a reference for HAMR design, and also provides a direction for improving thermal structures for high-density HAMR recording," Xu says.

Explore further: With neutrons, scientists can now look for dark energy in the lab

More information: Xu, B. X., Liu, Z. J., Ji, R., Toh, Y. T., Hu, J. F. et al. Thermal issues and their effects on heat-assisted magnetic recording system (invited). Journal of Applied Physics 111, 07B701 (2012). dx.doi.org/10.1063/1.3671421

add to favorites email to friend print save as pdf

Related Stories

TDK sees hard drive breakthrough in areal density

Oct 03, 2012

(Phys.org)—TDK has realized increased areal density of its hard disk drives. TDK has set a new record, compared to previous areal density at 1Tbit/inch2, with the new stat of increased density to 1.5Tbit ...

World record data density for ferroelectric recording

Aug 17, 2010

Scientists at Tohoku University in Japan have recorded data at a density of 4 trillion bits per square inch, which is a world record for the experimental "ferroelectric" data storage method. As described the journal Applied Ph ...

Recommended for you

How to test the twin paradox without using a spaceship

14 hours ago

Forget about anti-ageing creams and hair treatments. If you want to stay young, get a fast spaceship. That is what Einstein's Theory of Relativity predicted a century ago, and it is commonly known as "twin ...

User comments : 0

More news stories

Progress in the fight against quantum dissipation

(Phys.org) —Scientists at Yale have confirmed a 50-year-old, previously untested theoretical prediction in physics and improved the energy storage time of a quantum switch by several orders of magnitude. ...

Meteorites yield clues to Martian early atmosphere

(Phys.org) —Geologists who analyzed 40 meteorites that fell to Earth from Mars unlocked secrets of the Martian atmosphere hidden in the chemical signatures of these ancient rocks. Their study, published ...

Down's chromosome cause genome-wide disruption

The extra copy of Chromosome 21 that causes Down's syndrome throws a spanner into the workings of all the other chromosomes as well, said a study published Wednesday that surprised its authors.