Slashdot Mirror
Spintronics May Lead to Quantum Microchips
Rashan writes "A Scientific American article which waxes poetic about the possibility of microchips which use the "spin" of an electron to perform their functions." An excellent explanation of a complex subject.
props to scott bakula! the original quantum microchip
-
fp
The "spin" of an electron? Oh, please. Next thing they're going to claim that they can harness the energy of a black hole to power the world's computers. If you want to impress me, prove that black holes or electrons actually exist. Otherwise I fail to see why this unsubstantiated garbage actually gets posted on Slashdot.
Im ready for Quantum Entanglement Networking, heh zero ping time, and nearly unlimited bandwidth, and unlimited range, till then im gonna be stuck with dial up, seeing as how i live on the outskirts of nowhere
"The United States has no right, no desire, and no intention to impose our form of government on anyone else." - Bush 05
Electronics use electrons, so spintronics must use...spintrons?
Karma: Good (despite my invention of the Karma: sig)
...the foundation of spintronics... wasnt the foundation of spintronics and 80's techno group?
Is it just me or was Slashdot slashdotted or something for at least the last five minutes? I could not get the front page to load... what is up with that.
With your feet in the air and your head on the ground, try this trick and spin it.
Your head will collapse if there's nothing in it and you'll ask yourself:
Where is my mind?
No, that's not a bug in the code, your computer must be dizzy.
Jessica Alba post
... but then, so could about four or five thousand other men.
Then a strange chip would be perfectly normal!
You are not the customer.
Hehe, I would give you +1 Funny if I could.
Spintronics??? I had the idea of sticking my computer in the washing machine months ago. If only I'd patented it.
quantum computing?
we already have that:
fork()
DNA is the ultimate spaghetti code.
I'm afraid it is only spin.
sig is
You'll have to take that magnet out of here, this is a 'no spin' zone.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
How sensitive to electro/magnetic interference would such a chip be?
In times when my neighbor can fry all my PCs with a home-made impulse gun I'd be more interested in a light-based chip.
Will us nerds who do tech support begin to be called spin-doctors by the press now?
"The United States has no right, no desire, and no intention to impose our form of government on anyone else." - Bush 05
I believe that Maytag was the first to use
spintronics.
Watch out all you chip companies, Big Bad Maytag
will sue you all for IP violations!
(In reality though wouldn't it be nice if all computers were as dependable as washing machines?)
Service guarantees Citizenship! Questions Guarantee GITMO.... Amerika Uber Alles!
baby right round.
Like a record baby, right round, round round.
I want your LoooOOOooOOOoooOOOOve,
I need your LooOOOooOOOoooOOOOve,
All I know is that to me, you look like you're havin' fun,
Open up your lovin' arms,
Watch out here I come.
Heh, if only i hadn't spent my mod points this morning.
Hey,
Uranium is a GREAT thing! Good for promoting hair loss, tooth loss AND rectal bleeding!
Arsenic has merely suffered from a lack of a good PR company. It needs a jingle something like
"Arsenic will make your nosy neighbor sick,
and if you hate your family head, use Arsenic
to make them dead! AAAARRRSENNIC!!"
Picture the above with a snappy jingle, I think Arsenic sales would go through the roof.....
As for Poison Ivy? She was REALLY DAMN hot in Batman so don't dis her either!
Service guarantees Citizenship! Questions Guarantee GITMO.... Amerika Uber Alles!
Of course you will have to power it via the static electricity generated while using a hula hoop while wearing a polyester leisure suit.
--
As a matter of fact, I am a lawyer. But I play an actor on TV.
A little static electircity changing an electron or two in your computer, and you'll have to re-authenticate it.
Forty-five bucks for that overblown piece of shit by that fucking blow-hard?
Give him the goatse.cx picture link and tell him to wank himself.
I miss the old Scentific American, when the articles were more technical and more accurate.
...where the executives used the spin of "stock options" to perform their functions.
I'm not familiar at all with the field, so here's a dumb question:
If they are going to use electron spins to keep track of information, how are we to encapsulate the electrons, with other electrons? Didn't the article say that they affect all other electrons in the area?
It was only you who had a problem.
That was all I wanted to say.
since they're spinning, do the electrons get sick and barf up their nucleus?
-motardo
That's insightful?!?
Maybe if the moderator was a native galimatias speaker... cause in galimatias, "Insightful" might just mean "Funny".
GMR heads use the spin of electrons to detect changes in the magnetic field on the surface of the discs.
Napster-to-go says "Fill and refill your compatible MP3 player", which is a lie. It's not MP3. It's WMA with DRM.
Coming to the diagnostic section of your local software store in 2035: Norton Spin Doctor 1.0
"What is the sound of one belly slapping?"
Courtesy of About 420
Connotative Use/Meaning
420 is a phreak's (and not just a hippie's) favorite number for a
variety of reasons, or maybe for no reason at all, but colloquially
the number says pot -- let's smoke pot, or someone's smoking
pot, or gee, i really like pot, or time to smoke pot, either by
time (4:20 a.m. or p.m.), date (April 20th), or otherwise (e.g. State
Route 420). April 20th at 4:20 is marked by annual events in
Mount Tamalpais, CA (an informal gathering); Marin Conty, CA
(the 420 Hemp Fest); Ann Arbor, MI (the Hash Bash); and
Washington, D.C. (buildup towards the July 4th Smoke-In).
Original Source(s)
Conventional wisdom: The most common tale is that 420 is the
police radio code or criminal code (and therefore the police call)
in certain part(s) of California (e.g. in Los Angeles or San
Francisco) for having spotted someone consuming cannabis
publicly, i.e. pot smoking in progress; that local cannabis users
picked up on the code and began celebrating the number temporally
(esp. 4:20 a.m., 4:20 p.m., and April 20); that the number became
nationally popularized in the late 1980s and, more ferverently, in
the early- to mid-1990s; and is colloquially applied to a variety of
relaxed and/or inspired contexts, including not only pot
consumption but also a good time more generally (in contrast to
the drug war surrounding).
Conventions are legends: 420 is not police radio code for
anything, anywhere. Checks of criminal codes (including those of
the City of San Francisco, the City of Los Angeles, Los Angeles
County, the State of California, and the federal penal code) suggest
that the origin is neither Californian nor federal (the two best
guesses). For instance, California Penal Code 420 defines as a
misdemeanor the hindrance of use (obstructing entry) of public
lands, and California Family Code 420 defines what constitutes a
wedding ceremony (Marco). One state does come close: The
Illinois Department of Revenue classifies the Alcoholic Liquor Act
under Part 420, and the Cannabis and Controlled Substances Tax
Act are next, under Part 428. (RB 5/19/99)
True story?: According to Steven Hager, editor of High Times,
the term 420 originated at San Rafael High School, in 1971,
among a group of about a dozen pot-smoking wiseacres who
called themselves the Waldos. The term 420 was shorthand for the
time of day the group would meet, at the campus statue of Louis
Pasteur, to smoke pot. ``Waldo Steve,'' a member of the group who
now owns a business in San Francisco, says the Waldos would
salute each other in the school hallway and say ``420 Louis!'' The
term was one of many invented by the group, but it was the one
that caught on. ``It was just a joke, but it came to mean all kinds of
things, like `Do you have any?' or `Do I look stoned?' '' he said.
``Parents and teachers wouldn't know what we were talking about.''
The term took root, and flourished, and spread beyond San Rafael
with the assistance of the Grateful Dead and their dedicated cohort
of pot-smoking fans. The Waldos decided to assert their claim to
the history of the term after decades of watching it spread, mutate
and be appropriated by commercial interests. The Waldos contacted
Hager, and presented him with evidence of 420's history, primarily
a collection of postmarked letters from the early '70s with lots of
mention of 420. They also started a Web site, waldo420.com. ``We
have proof, we were the first,'' Waldo Steve said. ``I mean, it's not
like we wrote a book or invented anything. We just came up with a
phrase. But it's kind of an honor that this emanated from San
Rafael.'' Maria Alicia Gaura for the San Francisco Chronicle,
4/20/00 p. A19; and thanks to Noah Cole for the submission
Alternate explanations
There are a variety of other explanations, all much more interesting
than police code, and many plausible. Some are more likely uses
of the 420/hemp connection rather than sources of it, such as the
score for the football game in Fast Times at Ridgement High,
42-0.
Known Myths: It isn't police code (see above). There are 315
chemicals in marijuana, not 420. And although tea time in
Amsterdam is rumored to be 4:20, it is actually 5:30 (Gerhard
den Hollander).
Sixties Songs: For instance, Bob Dylan's famous Rainy Day
Women #12 and 35 is a possible reference, or source --
12x35=420. And Stephen Stills wrote (and Crosby Stills Nash
& Young performed) a song 4+20 (first recorded 7/16/69,
released on Deja Vu 3/11/70) about an 84-year-old
poverty-stricken man who started and finished with nothing.
(Thanks to Sherry Keel 12/6/98.) Dylan aslo mentions 4 and
20 windows in The Balland of Frankie Lee and Judas Priest
(on John Wesley Harding).
Older Verse: But 420 in poetry is older than that - Greg
Keller notes the old nursery rhyme line, four and twenty
black birds baked in a pie. Revelation 5:14 (in the King
James Version of the Christian Bible) reads, And the four
beasts said 'A-Men.' And the four and twenty elders fell down
and worshipped him that liveth for ever and ever. (Travis
Spurley 2/15/99) And in Midnight's_Children, Salman
Rushdie wrote, Inevitably, a number of these children failed
to survive. Malnutrition, disease and the misfortunes of
everyday life had accounted for no less than four hundred and
twenty of them by the time I became conscious of their
existence; although it is possible to hypothesize that these
deaths, too, had their purpose, since 420 has been, since time
immemorial, the number associated with fraud, deception and
trickery. (Comet 2/14/98) Comet's best guess is that this
refers to something in Indian mythology or numerology, since
the book is set in India and frequently involves Indian history,
culture, and religion. Given the high interest in Eastern
religion among the phish/dead community, this seems a likely
origin of 420's current significance.
Temporal Significance: Hands on analog clock at 4:20 look
like position of doobie dangling from mouth Larry in
Tuscan and Alex Mack 5/19/99). Disruptive students are out
of detention and safetly away from school by 4:20, also
rumored to be the time that you should dose to be peaking
when the Dead went on stage Hart. The Waldos were a
group of teens back in the 70's that lived in San Rafael, CA.
420 was the way they talked about pot in front of teachers,
non-smoking family members etc. Also it was the time of day
they could just go relax, and get baked. (PhunkCellar)
Jamaicans purportedly worked till 4 then walked home then
lit up. They would talk 420 like our parents talked about after
5. That's when partying began Larry in Tuscan). Albert (not
Abbie) Hofmann supposedly first encountered LSD at 4:20
p.m. on 4/19/1943 (Bart Coleman citing Storming Heaven by
Jay Stevens, recommended by Mickey Hart in Planet Drum).
Surrealist painter Miro was born April 20, 1893. And
www.filmspeed.com says the propoganda film Reefer
Madness has a copyright date of April 20, 1936 (i.e. 4/20).
(Patrick Woolford)
Misc: Could be that it comes from hydroponics, the practice
of cultivating plants in water often used by indoor marijuana
cultivators, since 4 is used for H on a calculator (420/H20).
(Nick Lowe 3/30/00) The number 80 (eight) is quatre vingt
(pronounced cah-truh vahn), meaning four (times} twenty.
Dan Nijjar 1/27/00 (No connection yet between the number
80 and pot. A quarter pound is roughly 120 grams, rounding
quarter-ounces to 7.5.) The titanic was supposed to arrive
4/20/1912. (Thanks to RB.) Perhaps the heavy use of vt420
terminals in the Berkeley area is to blame? (BTW, 420 in
binary code is 110100100.)
Ubiquitous?
Now there's a 420 Pale Ale. One of the late-97/early-98 Got
Milk ads featured a character eating cookies without milk and
then passing a sign that reads Next Rest Area 420 miles (as Ross
Bruning). Reportedly, all of the clocks in the movie Pulp Fiction
are stuck on 4:20. Shirts with the number 420 on the red-and-blue
interstate highway shield (Interstate 420?) have show up on the
sitcom Will and Grace (Paul Risenhoover 5/14/99) and in several
videos. UPS' labelling software has a 420 postal code legend for
next-day/2-day deliveries (which is how Phish tickets are sent).
(Jack Lebowitz 10/3/98) MTV's 1997 Viewer's Choice Award (for
the MTV Video Awards) was decided by calls to
1-800-420-4MTV. And by May of 1998, the number was
appearing in so many ads (eg Copenhagen 5/14/98 Rolling Stone
p54, Corvette p55 5/98 Car & Driver) that its presence is
presumed to be intentional. Many songs are around 4 minutes 20
seconds long (since many songs fall between 2:30 and 5:30),
including for example Pink Floyd's A Great Day for Freedom (on
The Division Bell, 1994), the Foo Fighters' My Hero, and
Smokin' from Boston's first album. There have also been some
420 references on The Simpsons. In the re-run episode aired on
April 20th, 1999 at a special time (probably in honor of those
college students staying in the holiday spirit
Flanders that Barney's birthday is April 20th. Also, the jackpot sign
in one part of the casino says $420,000. There are a couple less
concrete ones, but these two have to be legit, especially since they
decided to air THAT particular episode on 4/20/99. (Submitted by
Matt Meehan 4/21/99) And (as of Fall '99) the 60 free minutes that
Working Assets Long Distance offers, at the 7 cents per minute
rate, is $4.20 free. There's even a band named 420, and another
names . In the first fifteen pages of Karel Capek's novel War with
the Newts, a man diving under wonder stayed down for four
minutes and twenty seconds. Grant Garstka 1/6/00 At the
suggested retail price ($3.96) and Michigan (6%) sales tax, a deck
of Uno cards costs $4.20. Nic Boris 4:20 marks the first downbeat
of the drums in Led Zeppelin's epic Stairway to Heaven. (Dan
Harris) The bill authorizing force after the World Trade Center
attacks of 9/11/01 passed 420 to 1, and news reports in following
months noted many times that there are (or were then, anyway) 420
airports in the U.S. Allan Morris And don't forget that Adolf Hitler
was born on April 20, macabely celebrated (or at least
referenced) via the Columbine High School shootings.
Phish-related Occurances
Whatever the origin, the number appears frequently... For the
summer 1997 tour, TicketMaster service charges were $4.20. In
the Fall 1997 Doniac Schvice Dry Goods section, a limited edition
Pollack poster printed on 100% hemp is order number 420P. The
Great Went was 420 miles from Boston (former home of Phish).
The official logo includes 4 gills and 20 bubbles (Gringo
11/12/98). As of 6/15/97, including covers and originals, Phish
had performed a total of 420 songs (thought its 486 by 4/24/98).
(David Steinberg). Lawnboy is 420megs of memory. Patrick
Walker Phish's The Vibration of Life underlies a whirling loop
with Seven Beats per second (which makes 420 beats per minute.)
Trey has used the altered line woke up at 4:20 in Makisupa
Policeman, which also often indirectly celebrates 420ing, e.g. by
mention of goo balls. One of the funniest shirts around takes light
jabs at both the 4:20 phenomenon and the rumored evolution
(collapse?) of the Phish.Net (especially rec.music.phish) from
being Gamehendge to Flamehendge, and beyond. The first day of
the Great Went started at 4:20 (with Makisupa Policeman. (The
second day started late, at 4:37.) Noah Cole The first single from
Slip Stitch and Pass was played on WBCN 10/14/97 at 4:20 pm.
An uproar at 12/31/96 can be heard on tape during the 2001, in
response to an enormous digital clock (which was counting down
to midnight) reaching 11:55:40 and reading -4:20. (Yoda)
During the 9-12-00 2001, Trey hits the first riff right at 4:20 into
the intro jam. (Cal 2/25/01) Some mail order tickets for the 1997
New Year's run were in section 420. The first Mass Pike toll
leaving Oswego was $4.20. (Camille Heath ) And the standard
shipping for The Phish Companion through Amazon was
originally $4.20.
420 Shows: Phish performed on April 20 in 1989, 1990, 1991,
1993, and 1994. The first day of the Great Went started at 4:20,
although that was called a soundcheck by Trey after three songs.
The Jazzfest Harry Hood 4-26-96 started at about 4:20 reported by
Trevor. At Big Cypress, David Bowie was playing at 4:20 a.m.
And the one event during the hiatus (10/8/00 - ?) featuring all
four members - for Jason Colton's wedding - was 12/1/01, 420
from: http://www.phish.net/faq/n420.html:
Spintronics could mean the end of booting your computer. From the article:
More sophisticated storage technologies based on spintronics are already at an advanced stage: in the next few years, MRAM (magnetic random-access memory), a new type of computer memory, will go on the market. MRAMs would retain their state even when the power was turned off, but unlike present forms of nonvolatile memory, they would have switching rates and rewritability challenging those of conventional RAM.
Think about what this means! You will be able to turn off your MRAM computer and when you turn it back on, you won't have to boot it. The computer (its memory) would be in the state in which you left it. Think of how nice that'll be!
Of course, when Windows crashed everyday, you'd still have to boot it.
Here is a solution of that problem and how these two mcse sys admins routed around the problem by constructing a crude lathe to be used as a rudimentary weapon.
For a fairly detailed overview of quantum computers, see Brian Hayes' article "The Square Root of NOT".
The mind boggles at the power of a quantum parallel CPU and that's before some smart arse overclocks it.
I am a Karma Library.
Those of you who are interested in the future of alternative computing, including quantum computing, might want to check out Caltech's Computing Beyond Silicon Summer School program. The top minds from around the world will present the latest information about quantum, molecular, and DNA computing.
Instead of 0s and 1s we'll have +1/2 and -1/2!
"An excellent explanation of a complex subject."
In otherwords, you didn't understand it. The reason I can make this statement is that the Slashdot editors only make simple, unbiased claims when they have either no interest or no understanding of the subject matter. If the editor in question here had actually read the article and gotten a grasp of its "excellent explanation", I am certain we'd have a prediction about how this will lead to Lain-eque networks and hot-grits, all the while bitching about privacy and fairness in an area of quantum computers. Meanwhile, in another browser window, the editor is bitch-slapping whole threads and black listing users who disagree with them.
Don't worry, you're not alone. Quantum physics confuses everyone.
Why bother.
I just got to work here and tried to read that article... My head hurts now...
Megnetisation is the setting spin. In this technology they are taking about using a very small nmber of spins to do logic and represent data.
Pun not intended.
Noticed something in that article - they state that the hard disk read heads use GMR sensors - not quite accurate. They use a single unit spin valve. GMR devices consist of many layers stacked on top of each other, and, more pertinantly, they operate at large magnetic fields. The sensor used have a lower field for peak sensitivity, and the change in resistance in smaller. GMR is conventionally used in the literature to indicate large, multi-layer devices. [0]
One thing that the article glosses over slightly is the difficulty in construction. Well, it's not so much a dificulty, as a paradigm shift. The metal GMR structures are built vertically onto a substrate, and thus the working current flows perpindicular to the plane of the substrate. This is distinct from traditional semiconductors, where the principle direction of the working current is parrallel to the plane of the substrate.
The notable exception would be the spin FET, but they've not actually been built yet, so it's a little tricky to comment on.
One option that the article didn't mention is the possibily of generating a magnetic semi-comductor / metal by using a conventional magnetic insulator (such as NiO, MnO or Fe2O3), and dopeing, or otherwise adjusting the electrical properties [1].
My research is into combined ab initio and statistical mechanical models of ultra thin films of the magnetic insulators. Particularly interesting is what happens when a two atom thick layer of iron is put over an NiO surface - spin dependant electron transfer, which is interesting. All in all, most of my work is the blue sky / basic building block level.
My point is that the spintronic devices require a finre degree of control in construction - by thier nature, the magnetic structure is important. Oh, and as a kicker to this, the length scale for a defect in a magnetic lattice is around 20 or so times larger than it's affect on the electrical properties. Additionally, it seems likely (to me) that other routes to mass manufacture may have to be found.
In other words: These are going to cost more. Not just because they are new, but also because they are inherently more complicated devices that electronic semiconductore devices.
[0] Well, in PhysRev anyway. IEEE and similar may use a different nomenclature
[1] My calculations suggest that a layer of NiO 4 formula units thick, or thinner, will be a metal.
That was almost as funny as my joke.
Karma: Good (despite my invention of the Karma: sig)
can anyone post the article here!!
No, they use Spin-dependent electrons. This is spintronics, in a nutshell.
Up until now, almost all electronic devices have made use only of the electronic charge. Ie, amplifying it, switching on it, transferring it, etc.
Well, in a subtle manner, there is spin dependence in the above, due to Pauli exclusion, but that's buried in the quantum statistics.
Remember the electron is a spin-1/2 fermion, and hence has two possible states for a measure of it's spin in any given direction. Spin is an inherent property of many particles, with no classical analog, but you can think of it roughly as an angular momentum. Spin is quantized, unlike a spinning top. A spinning top is a classical system, which can have any rotational speed from 0 to any positive/negative values. (Negative means opposite direction of spin as a positive value).
Since the electrons are quantized spin-1/2 particles, there are only two measures of the spin angular momentum that are valid. +-(1/2)hbar where hbar is the Planck constant. Thus, an electron can only spin one way or another, there are no intermediate values (including no zero value, so it's ALWAYS spinning). Also note that this spin doesn't really represent the electron spinning about it's own axis, it's an inherently internal concept that's is actually quite involved.
These two values of spin of an electron can now be exploited in new devices. Right now the goal is to make devices that can inject electrons of one value of spin, and make transistors that work only for certain values of spin, or preserve spin parity, etc. Quantum computation would work nicely here too because the two states of spin are a good basis for representing a binary digit.
I haven't read the Scientific American article, so I don't know if I'm just repeating the obvious or not. But I'm a graduate physics student right now, and I hope to eventually work on some applications of spintronics. It is a currently buzzing field with much potential.
make world, not war
"For instance, even the earliest computer hard drives used magnetoresistance--a change in electrical resistance caused by a magnetic field--to read data stored in magnetic domains."
All earlier practical Hard Drives before the "discovery" of the GMR effect used Electromagnetic heads; wildly different practicalities than GMR heads. They were simple electromagnetic devices mounted on aerodynamic substrates; low impedance, wire wound affairs and definitely NOT magnetoresistive.
Did I miss something in the spin and magnetism physics relationship??
Sounds like the perfect chip for spindoctors to use. :)
Video Game cheats, hints a
...the possibility of microchips which use the "spin" of an electron to perform their functions.
I thought that was the basis of quantum computing? At least when I read about it 2 years ago it was..... called a qbit?
Everybody is talking about building quantumcomputers, but no one has thought of a way to stop the distorsion that occurs when making an electron spin. The are multiple ways to make it spin, on of them is using a magnetic field. This will influence the electrons nearby. Other methods do have the same effect. There are two ways to deal with this: 1. Find a method that will not create distorsion. So far, no one has been able to come up with a good solution. 2. Compromise the distortion in the software. This will reduce the extra speed, gained by using the quantum mechanics, to almost nothing. Therefor, untill we find a way to make the particles spin in one or two directions without influencing the others, we will not be able to use all the extra speed. Distorsion is not the only problem. The order in which the particles are made to spin will also influence the state of the particles. I didnt' read the article, so if this has been sad already, I'm sorry.
When'll linux try to assbackwords enginere the software get a half ass driver and be a mediocre OS at 400x the speed?
Only half kidding:
Imagine that programs
in a quantum computer can have bugs that
disappear as soon as you try to observe them.
In current programming there are sometimes problems that disappear as soon as you try to debug them, the disappearance apparantly caused by the interaction with the debugger program.
These bugs are called "Heisenbugs".
It just appeared to me that quantum programs could have actual Heisenbugs.
-------------------------------------------------
UNIX isn't dead, it just sme