Heat-assisted magnetic recording

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The English term heat-assisted magnetic recording ( HAMR , German  heat-assisted magnetic recording ) describes a method for storing information in magnetic materials, which is supposed to enable even greater data densities on hard drives . Seagate demonstrated laboratory technology with HAMR for the first time in the summer of 2002. In 2013, the first series models were announced, which are not available as of 2018.

The process

With HAMR, the domain into which data is to be written is first heated locally by a laser above the Curie temperature in order to keep the magnetic field required for a writing process as small as possible and to enable writing despite the weak super paramagnetic effect. As the magnetic points that store a bit become increasingly smaller, the superparamagnetic effect occurs at some point, in which the magnetic force is subject to heat and the ferromagnetic magnetization becomes unstable. Available thermally stable magnetic materials require higher coercive field strengths for the permanent magnetization of comparably large magnetic points. With conventional vertical recording, therefore, ever higher magnetic field strengths are necessary, whereby the limits of the realizable field strengths in 2013 are considered to be largely exhausted and impede further miniaturization. This limitation is circumvented with the help of heating. However, since the hard drive's protective lubricant evaporates when it is heated , the hard drive manufacturer Seagate wants to store supplies in nanometer-thin carbon tubes from which lubricant can be released onto the surface of the hard drive if necessary.

expectations

It is already speculated which storage capacity can be achieved using this technology. In 2007 Seagate still expected that capacities of 37.5 terabytes could be achieved by 2010. In October 2013, Seagate reduced this planning to up to 20 terabytes in 2.5-inch hard drives by 2020. That would be 10 times as much as the largest hard drive at the time of the announcement with around 2 terabytes (2.5 ") in 2016 conventional hard drives with a capacity of 10 TB are commercially available, but it is also reported that this technology could increase the number of head crashes and thus impair the quality of the hard drive.

Individual evidence

  1. ↑ a b 50 terabits per square inch . heise online, August 2, 2002.
  2. ↑ a b Boi Feddern: Seagate demonstrates Heat-Assisted Magnetic Recording. In: iX news. October 2, 2013, accessed October 3, 2013 .
  3. ^ Anton Shilov: Seagate Ships 35th Millionth SMR HDD, Confirms HAMR-Based Drives in Late 2018. In: anandtech.com. May 3, 2017, accessed July 31, 2017 .
  4. ↑ HAMR - technology for larger storage capacities ( memento of the original from March 16, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. . Hard drive test, June 10, 2013.  @1@ 2Template: Webachiv / IABot / festplattentest.de
  5. ↑ Alex Zaharov-Reutt: Seagate to offer 300 TB hard drive by 2010 . iWire, January 3, 2007, accessed October 3, 2013.
  6. ↑ From a 300TB Seagate drive to a 3TB one . Techworld January 5, 2007.