Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Science Technology

Individual Atom Memory Created 123

azav writes "University of Wisconsin-Madison Scientists have created "atomic scale" memory using individual atoms of Silicon." A cool photo can be found on the site as well.
This discussion has been archived. No new comments can be posted.

Individual Atom Memory Created

Comments Filter:
  • Bah! (Score:5, Funny)

    by DarkHelmet ( 120004 ) <mark&seventhcycle,net> on Saturday September 07, 2002 @05:42AM (#4211521) Homepage
    University of Wisconsin-Madison Scientists have created "atomic scale" memory using individual atoms of Silicon." A cool photo can be found on the site as well.

    Single atom memory? How stable do they REALLY expect that to be?

    Ha! What's the name of the technology? Alzheimer's Access Memory?

  • repost (Score:3, Informative)

    by Anonymous Coward on Saturday September 07, 2002 @05:52AM (#4211538)
    .. not to be too repetitive, but this was posted only a month ago..

    http://science.slashdot.org/article.pl?sid=02/08/0 8/0116255&mode=thread&tid=126 [slashdot.org]
  • about moore's law?

    And a brick wall?

    Methinks there is no higher density than bit-per-atom.

    hrm... bit per electron...

    • You just have to start storing multiple states in one atom. The Quantum Computing people have been talking about that for years.
      • If you are willing to accept false answers from a quantum computer being used as a signal processor, the signal you recieve will be from another universe...

        We can communicate with other universes.

        I can transmit messages to Perdos in parallel universes.

        No.

        You can not store and retrieve more than one bit in an atom using quantum states.
        • I wonder how the RIAA will handle 'IP protection' on quantum systems.. maybe that file _is_ britney spears.. or maybe its my accounts.. maybe britney doesnt exist.. we can only hope :) maybe its all in another universe.. who am i? whats going on waah why did i write all this?

          Damn Quantum computers

    • there is no no higher density than bit-per-atom.

      Doesnt this assume you can only store information in particles with mass? For instance, light can have wavelengths smaller than the "width" of an electron.
      • What is the width of an electron ?
        Hint: it's unknown (for the free electron). We only know that the electron is smaller then 10^-15 meters, compare this to the wavelength of visible light: 10^-6 meters. Visible light has HUGE wavelength (several thousand atom spacings)! Guess why we need UV and XUV etc. light for lithography...to get near atom size with light you actually need X-rays!
    • by Waffle Iron ( 339739 ) on Saturday September 07, 2002 @10:23AM (#4212006)
      about moore's law?

      And a brick wall?

      Methinks there is no higher density than bit-per-atom.

      6.02x10^23 Kb ought to be enough for anyone.

  • by Kredal ( 566494 ) on Saturday September 07, 2002 @06:11AM (#4211580) Homepage Journal
    "If you can read this, you're WAAAY too close!"
  • by jukal ( 523582 ) on Saturday September 07, 2002 @06:15AM (#4211588) Journal
    The article links to this article [wisc.edu] which describes better how it actually works.

    "Reading the memory consists of a simple, one-dimensional scan, because it is self-formatted into precise tracks. There is no need to search in two dimensions for the location of a bit. The signal is highly predictable since all atoms have the same shape and occur on well-defined lattice sites. That allows for a high level of filtering and error correction"

    "Writing is more difficult. While atoms can be positioned controllably at liquid helium temperature, that is much harder to achieve that at room temperature"

  • Just as long as you don't arrange atoms in a way that could, using some sort of algorithm, produce a recording of some popular music. Otherwise, the RIAA's nano-bots, will deconstruct your atoms.. with permission of the US government
  • by Subcarrier ( 262294 ) on Saturday September 07, 2002 @08:22AM (#4211776)
    In 1959, physics icon Richard Feynman predicted that all the words written in the history of the world could be contained in a cube of material one two-hundredths of an inch wide.

    And then we'd need a new search engine just to find the damn thing.

    Fortunately, the text would probably be stored in the innovative MS Word format, which guarantees that the physical size of the required storage capacity will remain constant over time, no matter what the information density of the storage medium.
  • by Typingsux ( 65623 ) on Saturday September 07, 2002 @08:58AM (#4211828)
    Says to the bartender "I think I lost an electron"

    Bartender replies "Are you sure?"

    Atom thinks for a second: "Yea I'm positive."

    • Just then, a rather negative looking chlorine atom walks in and sits down next to the recently robbed sodium: "I snagged it while you weren't looking. Gonna try to grab it back?"

      Sodium: "Nah. I don't want to be reduced to your level."
  • by Alsee ( 515537 )
    I had an incredibly insightfull and informative post to make, but I stored it on an atomic scale memory smaller than a spec of dust. Now I can't remember where I put it.

    -
  • Since most operating systems are 16 and 32 bit in nature, why do we continue to use binary memory? Why not have memory that can somehow represent 16 or 32 states?
    • Mostly for speed. Let's review our 1st year digital electronics course. Since computer operations (at least in modern-day chips) are done on the binary level, storing in 32/64/whatever bits levels would require whatever portion of the system is reading the memory block to convert this one psudo-bit (for lack of a better term) to digital before processing. This is equavilent to (for example) sampleing audio data (taking the voltage produced by a microphone or similar device, and converting it to 8/16/24 bits).


      In addition to requireing extra circuitry for decoding, this would require extra time. If you're wondering why CPUs don't just use various (16/32/64/whatever) voltage levels internally, then you really need a refresher course.


      Transistor -> voltage controlled current source. i.e. a transister (in most cpus, these are nmos/pmos pairs) will either be "conducting" or "not conducting" a current depending on voltage level at the gate. Although technically these conducting/non-conducting will have slightly different currents flowing though them, we cannot use these as various voltage levels for the next transister because we get into all sorts of matching problems, fan-in/out problems, and basically (for example) the number "26" would be represented by one voltage level here, a different one there, and another one based on what transisters or conducting, and how much. If you're wondering why we don't use resisters to solve some of these problems, you REALLY need to review - power dicipated = current * current * resistance = heat. 20B currents squared * 20B resistances = instant chip incineration.


      As a side note (actually two side notes) I beleive in the 40s they were experimenting with computers which used 10 voltage levels because that was the natuaral thing to do, until someone suggested using binary/boolean value which until that time were just a mathmatical curiosity than a dicipline taken seriously. I don't have references on hand ot back this up, but I think i remember reading something to that effect. The other side note is that many modems (even today) use variable-level voltages ot communicate. This is because the speed limiting factor effecting modems is line quality and length. It takes a relativly long time to force the line to any particular voltage, and so the modem makes these voltages count by encoding multiple levels. Ex. 9600bps modem uses 12 phase angles, four of which have two voltage levels, alowing to transmit 16 bits in one cycle (Stallings, Data & Computer Communications, 6th, p145). This is also why some modems (ex 56k) will only connect at (ex) 24k if excessive line noise prevents reliable encoding on many voltage levels.


      The second reason we don't use variable levels in memory storage is error control. 1/0 values are screwed up enough by line noise, magnetic fields, and what have you. Imageine how difficult a time a machine would have dtermining "is that atom 23456 picometers about the base or 23457?"

      As photonics emerges as a network technology though, I'm wondering if there is something like a "photo-transister" that will block or allow passthrough of light if light is present at a gate of a certain wavelegth. I know extreamly little about photonics, but if this possible then maybe multiple bits can be transmitted via multiple wavelengths inside a light-based (as opposed to electricity based) processor. Anyonw working on something like this?

      Anyway, I hope this helps!

      KeggInKenny

  • Umm... (Score:2, Interesting)

    by BoojiBoy0 ( 596932 )
    If those are silicon atoms in the photo then what are the grooves in between the rows of atoms?
    • Smaller atoms? Mercury is pretty big.
    • Actually I think the backdrop is a sheet of silicon atoms and the little dots mark the absence of an atom.
    • Fred is almost right. The holes in the photo mark the absence of an material that is the size of an atom. I think you have to know a bit how how information is stored on optical technologies such as CD's and DVD's. They use LED's to burn pits and valleys in a polymer type material. Then another LED with less power comes along and reads where there is a pit (1) and where there is a valley (0).

      As to the grooves, check this reply in the thread. " This has more details (Score:5, Informative) by jukal " Sorry I don't know how to link directly to the reply.
  • If the picture is of atoms, what is under them?

    I've always wondered that when I see an electron shot like this. Anyone know?
  • Someone (one of the few people who made an *intelligent* reply, anyway) Mentioned memory density. Out of curiosity I decided to figure out exactly how much data per square inch you could fit using this tecnique... Silicon has a van der Waals (minimum, non-bonding) radius of 210pm, or 2.1e-10 meters (8.27e-9 inches). That means the closest you could possibly pack them is 4.2e-10 meters on-center (1.65e-8 inches). That means you can pack about 60,400,000 silicon atoms in single file, or a whopping 3,600,000,000,000,000 atoms per square inch! That boils down to about 415.7 terabytes! Comparatively, current holographic memory systems can (last I checked) reliably store up to 25.6 megabytes per square inch, but of course it has the added feature of using the full volume of the media, and extreamely fast read/write times. =Smidge=
  • There's a PDF of the real journal article [iop.org] available from Nanotechnology's site.

    In the article they say that their atomic memory has an energy density of 250 terabits per square inch (compared to 100 gigabits per square inch for a hard drive). A CD-ROM has 14 square inches of recordable area. If one were to use this technique on a surface the size of a CD-ROM, that would give:

    (14 square inches) * (250 terabits/square inch) / (8 bits/byte) = 437.5 terabytes

    Incredibly huge, but I'm sure there's a number of people who would still be able to fill it up.
  • I hate it when all the guys bring their girlfriends to the LAN-Parties.
  • For those who missed it [slashdot.org], their 778 gigabyte database of the complete Awari game tree could be stored on a piece of silicon approximately 4mm square. Wait, that's just on one side! Sweet, we'll keep MP3s on the other 778 gig side.

    (0.778 terabytes) / ((250 terabits/sq.inch) / (8 bits/byte)) = 0.024896 sq.inch =~ 4mm square
  • Cos atoms have a habit of moving about.

  • Call the copyRight police! I just found my latest script embeded in that atomic pattern (photo) - it's backwards & encrypted, but I'm sure it's mine! ............... - just beacuse you're paranoid, it doesn't mean that the world is NOT out to get ya! -

"And remember: Evil will always prevail, because Good is dumb." -- Spaceballs

Working...