IBM Claims Spintronics Memory Breakthrough 77
CWmike writes with this excerpt from ComputerWorld: "In a paper set to be published this week in the scientific journal Nature, IBM researchers are claiming a huge breakthrough in spintronics, a technology that could significantly boost capacity and lower power use of memory and storage devices. Spintronics, short for 'spin transport electronics,' uses the natural spin of electrons within a magnetic field in combination with a read/write head to lay down and read back bits of data on semiconductor material. By changing an electron's axis in an up or down orientation — all relative to the space in which it exists — physicists are able to have it represent bits of data. For example, an electron on an upward axis is a one; and an electron on a downward axis is a zero. Spintronics has long faced an intrinsic problem because electrons have only held an 'up or down' orientation for 100 picoseconds. A picosecond is one trillionth of a second [one thousandth of a nanosecond.] One hundred picoseconds is not enough time for a compute cycle, so transistors cannot complete a compute function and data storage is not persistent. In the study published in Nature, IBM Research and the Solid State Physics Laboratory at ETH Zurich announced they had found a way to synchronize electrons, which could extend their spin lifetime by 30 times to 1.1 nanoseconds, the time it takes for a 1 GHz processor to cycle."
Re:Was it really necessary... (Score:0, Informative)
Was it really necessary for you to type 'Was it really necessary' twice? You could have just put an ellipse before the second part, especially since you ended the subject with an ellipse.
Re:etch a sketch? (Score:4, Informative)
I mean how hard I can shake it compared to the mass and energy of a tiny spinning particle, it could start spinning a different way, right?
LOL you wish. The story of chemistry and physics would be a lot different if that were true for protons. I've fooled around with proton magnetometers and NMR machines in chemistry lab and its not so simple to align proton spins. In fact its really freaking hard and energy intensive to align particle spins in general, not just proton spins. This would make an awesome basis for a hard sci-fi story, however. Someone please write a story about a steampunk NMR machine, so I can buy it. I think a Nikola Tesla who invented a steampunk NMR machine in 1870 would be much more interesting than yet another "vampire Tesla". My brain is feeling especially warped today and I'd also like to request a pre-quel involving a steampunk fourier transform infra red spectroscopy analyzer. I would have to think for a minute if there's any technical reason why Fourier himself couldn't have built a FTIR in his era. Hmm glowing charcoal as a IR source, and an early thermometer and lens arrangement as a ghetto IR bolometer, feeding reams of measurement data to hundreds of human clerks making calculations for years to generate each IR spectra, plus or minus an analytical engine or two... Hell a Beowulf cluster of analytical engines...
As for aligning electron spins like this article its still a huge PITA but the electromagnetic world depends on it. I can't think of any ferromagnetic material that can be (de)magnetized by waving it around... hammer blow level impact will realign the domains but just shakin it isn't going to do it. The reason why can be found on the wikipedia article for coercivity where basically the stuff you make recording media out of doesn't want to demagnetize without a serious fight.
Re:Likely not (Score:5, Informative)
Give me some science on it and tell me some more details.
Since they didn't give a link to it, here's the citation for the paper in question: M. P. Walser, et al., "Direct mapping of the formation of a persistent spin helix", Nature Phys., 2012 (accepted, in press). You can read all of the wonderfully gritty, and hard-to-parse, details in that paper.
If you want to learn more about the science behind spintronics, feel free to peruse:
M. Johnson and R. H. Silsbee, "Interfacial charge-spin coupling: Injection and detection of spin magnetization in metals", Phys. Rev. Lett. 55: 1790-1793, 1985
M. N. Baibich, et al., "Giant magnetoresistance of (001)Fe/(001)Cr magnetic superlattices", Phys. Rev. Lett. 61: 2472-2475, 1988
G. Binasch, et al., "Enhanced magnetoresistance in layered magnetic structures with antiferromagnetic interlayer exchange", Phys. Rev. B 29: 4828, 1989
S. Datta and B. Das, "Electronic analog of the electrooptic modulator", Appl. Phys. Lett. 56: 665-667, 1990
J. Kikkawa and D. Awschalom, "Resonant spin amplification in n-type GaAs", Phys. Rev. Lett. 80: 4313, 1998
B. T. Jonker, et al., "Robust electrical spin injection into a semiconductor heterostructure", Phys. Rev. B 62: 8180-8183, 2000
A. T. Hanbicki, et al., "Efficient electrical spin injection from a magnetic metal/tunnel barrier contact into a semiconductor", Appl. Phys. Lett. 80: 1240, 2002
S. van Dijken, et al., "Room temperature operation of a high output current magnetic tunnel transistor", Appl. Phys. Lett. 80: 3364-3366, 2002
X. Jiang, et al., "Optical detection of hot-electron spin injection into GaAs from a magnetic tunnel transistor source", Phys. Rev. Lett. 90: 256603, 2003
J. Schliemann, et al., "Nonballistic spin-field-effect transistor", Phys. Rev. Lett. 90: 146801, 2003
B. A. Bernevig, et al., "Exact SU(2) symmetry and persistent spin helix in a spin-orbit coupled system", Phys. Rev. Lett. 97: 236601: 2006
X. Lou, et al., "Electrical detection of spin transport in lateral ferromagnet–semiconductor devices", Nature Phys. 3: 197-202, 2007
M. Holub, et al., "Electrical spin injection and threshold reduction in a semiconductor laser", Phys. Rev. Lett. 98: 146603, 2007
I. Appelbaum, et al., "Electronic measurement and control of spin transport in silicon", Nature 447: 295-298, 2007
M. Duckheim and D. Loss, "Resonant spin polarization and spin current in a two-dimensional electron gas", Phys. Rev. B 75: 201305, 2007
B. Behin-Aein, et al., "Proposal for an all-spin logic device with built-in memory", Nature Nano. 5: 266-270, 2010
J. Wunderlich, et al., "Spin Hall effect transistor", Science 330: 1801-1804, 2010
How about a blurb about spintronics already being used in modern hard drive read heads?
I can do better than a blurb, I can provide you with references to the underlying science:
M. Julliere, "Tunneling between ferromagnetic films", Phys. Lett. 54: 225-226, 1975
J. S. Moodera, et al. "Large magnetoresistance at room temperature in ferromagnetic thin film tunnel junctions", Phys. Rev. Lett. 74: 3273-3276
W. H. Butler, et al., "Spin-dependent tunneling conductance of Fe/MgO/Fe sandwiches", Phys. Rev. B. 63: 054416, 2001
J. Mathon and A. Umerski, "Theory of tunneling magnetoresistance of an epitaxial Fe/MgO/Fe (001) junction", Phys. Rev. B. 63: 220403, 2001
M. Bowen, et al., "Large magnetoresistance in Fe/MgO/FeCo(001) epitaxial tunnel junctions on GaAs(001)", Appl. Phys. Lett. 79: 1655, 2001
S. Yuasa, et al., "Giant room-temperature magnetoresistance in single-crystal Fe/MgO/Fe magnetic tunnel junctions", Nature Mater. 3: 868-871, 2004
S. S. P. Parkin, et al., "Giant tunnelling magnetoresistance at room temperature with MgO (100) tunnel barriers" Nature Mater. 3: 862-867, 2004
S. Ikeda, et al., "Tunnel magnetoresistance of 604% at 300 K by suppression of Ta diffusion in CoFeB/MgO/CoFeB pseudo-spin-valves annealed at high temperature", Appl. Phys. Lett. 93: 082508, 2008