Print 15 comment(s) - last by patentman.. on Dec 1 at 1:51 PM

Fujitsu claims thermal assisted magnetic recording is the next big thing in ultra-high density

Fujitsu Computer Products of America, Inc. has recently announced that it has successfully developed an optical element which will compliment thermal assisted magnetic recording in future hard disk drives.

Currently many hard disk drive manufacturers are utilizing perpendicular magnetic recording technology to pack bits tighter on to platters enabling higher capacity drives but the negative effects of writing to closely positioned bits is still evident even with the perpendicular recording method. This mainly due to the coercivity of magnetic media.

Thermal assisted magnetic recording uses a combination of optical and magnetic recording technologies, as the name implies, to handle the adverse effects of writing to magnetic platters by focusing heat on the specific bit that is to be written to. The heat is produced by the optics while the magnetic recording head takes over in data transfer. A detailed white paper [PDF] on this technology is available on Fujitsu's website which explains the background of the technology.

Though still in the development stages, this announcement gives us hints on what to expect in the future from hard disk drive technologies. With a 1 terabit per square inch platter density hard drive manufacturers can achieve larger overall hard disk drive capacities.

Magnetic hard disk drives are still the primary medium for data storage and Hitachi GST claims it will announce 1TB hard drives by the end of 2006. Earlier this year Seagate was the king of capacity with its 750GB monster but it looks like Hitachi has had some tricks up its sleeve. We will bring you more information as it becomes available on Hitachi's terabyte product.

Comments     Threshold

This article is over a month old, voting and posting comments is disabled

Isn't it...
By Aikouka on 11/30/2006 3:38:56 PM , Rating: 3
I read about this earlier on Betanews and isn't it that Fujitsu's announcing they found a way to break the 1TB per square inch barrier, not that they are necessarily taking it to that?

The article I read talked about how the maximum storage capacity for parallel recording was 1TB/in^2 because of how any smaller the small iron flakes would lose their charge too quickly after cooling down or something along those lines. However, this new optical method from Fujitsu is supposed to help alleviate that issue, but Fujitsu hasn't made a laser that they deem small enough for it yet as they want a 60nm x 60nm laser, but their current one was a 80nm x 60nm if I remember correctly.

Just thought I'd throw them tidbits out there.

RE: Isn't it...
By bluefmc on 11/30/2006 4:11:39 PM , Rating: 4
sorry to nitpick, but it's 1 Tb (terabit) not 1 TB (terabyte). there are 8 bits in a byte.

RE: Isn't it...
By patentman on 12/1/2006 1:51:59 PM , Rating: 2
And its not that the iron flakes would lose their "charge."

1st: Iron is rarely used in magnetic media except as an additive or as a Ferrimagnetic or Antiferrimagentic layer in Magneto-optical media. The #1 mater for the recording layers of a magnetic recording material is CoCr, either alone or with minor ternary or quaternary additions.

2. The problem with parallel recoring is that to increase recording density beyond what it is currently requires that the grain size of the grains within the magnetic recording layer be reduce to below the superparamagnetic limit. That is, the grain size has to be reduced to the point at which the material goes from exhibiting ferromagnetism (useful for magentic recording medium b/c you can orient domains) to superparamagnetism (not useful for magnetic recording because domains are ordered almost randomly.

By oTAL on 12/1/2006 11:25:15 AM , Rating: 2
I hate Sony just as much as the next guy, but you got to give them credit on this one... they touted this technology for over a decade on their minidiscs - opto-magnetic recording... This is probably a hugely more advanced version, but the concept remains the same, and sony was the first company (that I know) to use it.

RE: Sony
By patentman on 12/1/2006 1:42:20 PM , Rating: 2
Actually magneto-optical recording and thermally assisted magnetic recording are two entirely different technologys. Easy to see why you might get them confused though.

RE: Sony
By patentman on 12/1/2006 1:44:12 PM , Rating: 2
See the first paragraph of this article

RE: Sony
By patentman on 12/1/2006 1:46:11 PM , Rating: 2
Lol, I just realized the article I linked to was the one already in the DT articles. My bad...

Thats HUGE!
By swtethan on 11/30/2006 3:21:28 PM , Rating: 3
I have a hard time filling up my 300GB drive with stuff. I guess this would be a good thing for HTPC owners.

RE: Thats HUGE!
By therealnickdanger on 11/30/2006 3:35:05 PM , Rating: 2
Yes indeed! I've intentionally avoided buying 500+GB HDDs for the sole reason of waiting for 1TB HDDs. 2TB RAID6, here I come! Now my entire DVD collection can be ripped in full glory to the server along with lots of room for everything else!

RE: Thats HUGE!
By SexyK on 12/1/2006 9:22:14 AM , Rating: 2
You hit it on the head with HTPC users. Before I started recording OTA HD I would probably not have been able to fill up a 1TB drive, but now I'd buy one in a snap if they were available. HD recordings are ~10GB/hour... talk about a space-sucker.

By patentman on 12/1/2006 10:29:39 AM , Rating: 2
Hate to nitpick about this as well, but I used to examine patent applications drawn to magentic recording media for a living. The article states that magnetic storage density is limited "mainly due to the coercivity of magnetic media." This is oly 1/2 the truth.

The main problem that limits magnetic storage density is an effect called intergranular exchange coupling. Essentially, this effect is interference that occurs when the magnetic field of a grain in the media interacts with the magnetic fields of surrounding grains, causing these fields to distort and become unstable.

There are several ways to address this problem. Initially, non-magentic or weakly magnetic elements, such as chromium, were co-deposited with the magnetic material in concentrations that resulted in precipitation of the non-magentic material between grains. Thus, the non-magentic metal material essentially shields each grain from the magnetic field of surrounding grains, and vice versa.

As the desire for increased storage density became more paramount, companies started using coercivity enhancing techniques to improve the stability of the magnetic fields of the grains of a magnetic recording medium (think of coercivity as an indication of the strength at which a magnetic domain is held in a given direction). Several of these techniques exist. First, coercivity enhancing elements, e.g., Pt and Pd have been added to the magnetic layer to increase coercivity. Unfortunately, many of these coercivity enhandcing elements are either extremely expensive (e.g. Ruthenium) or resulted in a reduction in signal to noise ratio.

As an alternative or supplement to coercivity enhancing elements, the use of "pinning" layers underneath the magnetic layer has also been used. A pinning layer is a magentic layer with magnetic domains with high coercivity pointed normal to the magnetic recording layer. The magnetic fields from the soft magentic layer increase the coercivity of the magnetic fields of the magentic reocrding material in one direction, e.g., normal to or in plane with the surface of the recording layer.

Thermally assisted magnetic recording media have been known for some time as well. Essentially, this technology employs a magnetic material that has very high coercivity at comparatively low temperature, and lower coercivity at high temperature (ok, all magentic materials exhibit a reduction in coeercivity at high temperature, but in this case the materials utilized exhibit a more pronounced effect). Accordingly, when the disk is in recording mode a light (e.g., laser) heats up the surface of the media to reduce coercivity, which enables the magnetic head to write data (orient domains) easily). Whe the light is removed, the media cools and the written bits are oriented more strongly in position due to the corresponding increase in coercivity as a result of the reduction in temperature.

By DrDisconnect on 12/1/2006 1:22:26 PM , Rating: 2
Nice and interesting explanation.

It seems to me that this technology will be more error prone for users who write and rewrite files frequently as the heating cycle will have the potential to eventually weaken the coercivity of adjacent information that is not being written. Obviously not a concern if you write massive files such as movies to your disk and just read them.

Any thoughts?

By patentman on 12/1/2006 1:41:31 PM , Rating: 2
The repeated heating and cooling isn't likely to cause any problems. It might cause some stress to the platter, but not a lot. The polycarbonate or glass substrates used nowadays are more than strong enough to handle it.

Hope that answered your question, I'm very tired today and can;t really think to straight.

The color Purple...
By Basilisk on 11/30/2006 4:27:58 PM , Rating: 3
I'm impressed they're going straight for "magentic recording technologies", skipping "mauvic" and "chartreusic"! Wonder if that will affect photo storage??? :)

Oh... never mind.....

Hitachi 1tb
By electriple9 on 11/30/2006 8:13:31 PM , Rating: 2
I hope Hitachi releases their 1tb hard drive real soon. And will be affordable.

"I'd be pissed too, but you didn't have to go all Minority Report on his ass!" -- Jon Stewart on police raiding Gizmodo editor Jason Chen's home
Related Articles

Copyright 2016 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki