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New Nanodevice Creates a Near Perfect Electron Stream
SchrodingerZ writes "Scientists from the National Physics Laboratory of the United Kingdom have teamed up with the University of Cambridge to create a new electron pump that creates a single electron stream. "The device drives electrical current by manipulating individual electrons, one-by-one at very high speed." The pump takes single electrons, and pushes it over a barrier with an indent for the electron to fall into, and is then sent to the opposite side of the barrier with astounding precision. "By employing this technique, the team were able to pump almost a billion electrons per second, 300 times faster than the previous record for an accurate electron pump set at the National Institute of Standards and Technology (NIST) in the USA in 1996." Although the current was very small (150 picoamperes), this event could cause a shift from the ampere measure of current to a smaller, more precise unit of measurement for electrical current."
NPL web site appears to be offline at the time of this post. Maybe they couldn't handle the deluge of electrons headed their way. Science Daily link okay though.
Free energy, a new golden age ... If they can manipulate individual electrons then for sure they can manipulate individual molecules. This is even greater than sliced bread.
http://en.wikipedia.org/wiki/Maxwell's_demon
#t33 h33 lol#
The last sentence was literally one of the stupidest things I've ever read here.
"The pump takes single electrons, and pushes it over a barrier with an indent for the electron to fall into, and is then sent to the opposite side of the barrier with astounding precision. "
What is pushed over the barrier? What is sent to the opposite side of the barrier?
Sentences like this need rewriting, at the very least until they actually make some semantic sense.
Too bad no one seems to be able to use this technology to make a Moray Valve (link).
Can any science/physics gurus tell me what sort of practical applications this has?
We focus protons the same and we can start catching some ghosts.
Who you gonna call? SCIENCE!
With this, we can replace the present analog definition of the ampere, with a digital definition. One ampere is 1 coulomb of charge flowing per second. If we know how many electrons flow by per second, we can multiply by the charge of the electron to get the current in amperes.
I notice that it is a NEAR perfect stream. Would the perfect stream consist of only particles and no waves?
could cause a shift from the ampere measure of current to a smaller, more precise unit of measurement for electrical current
This made no sense to me, and it turns out that what the article says is that one might want to formulate a new definition of the ampere. What do the editors do, really?
Swedish plasma phys. PhD student; MSc EE; knows maths, programming, electronics; finance interest; seeks opportunities
A billion electrons per-second = 1x10^9 which is a lot less than 1A.
A billion electrons per-second = 10^9/6.241x10^18 = 0.160nA = 160pA = 160x10^(-12) A (160 pico-amperes so pretty much the number in the article).
So while this might be a whole wack load electrons for this type of device it really is not much.
Also it might make you respect your hose wiring a little more.
Your 200A house service is (200*1A) = 1.2482x10^21 electrons per second.
The idea here is to define the ampere as N electrons per second. This may make that possible. The number is around 6.241 Ã-- 10^18 electrons per second. Direct counts of electrons allow a precise, repeatable way to define an amp.
The goal is to define the fundamental units from measurable properties of the universe, so that reproduceable standards can be constructed. That's been achieved for time and length, but not mass. You can buy an atomic clock that gets its time measurement from the definition of the second. (HP used to make those, but that business was sold off from Agilent in 2006.) There's a method with a Kr-86 light source and interferometers to count out a meter in wavelengths of light. But there's no corresponding standard for mass. Mass is tied to a physical 1Kg weight stored in France, and everything has to be traced back to that, with each successive derived standard kilogram a little less accurate.
A kilogram ought to be defined as N atoms of something, but atom counting isn't quite good enough yet. There's a plan to define mass through the Planck constant, which means tying the standard of mass to the standard of current.
Three fundamental units are sufficient to lock down all the other units, and this is a step towards doing that.
Amperes work just fine, thanks.
They work fine but they're defined in terms of the kg (force between two conductors) which is itself defined in terms of a standard kg.
If you can define the ampere in terms of number of electrons passing a point in a second (and actually count them) then you no longer need that standard kg.
I can calibrate my laboratory instruments using just the properties of the universe and some dimensionless constants.
Tim.
God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
An amp is 6.24150965(16)×10^18 (1 coulomb) electrons flowing past a point in one second.
How much energy difference is there between the two electron spin states?
Could a device like this electron streamer have added a nanodevice that sets the electron's spin before it's emitted? What's the practical minimum feasible energy consumption of setting each electron's spin? And thus the energy efficiency of such a spin setter.
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The problem isn't so much the (in)durability and bulk of the reference kilograms. It's more that our measurements of the kilograms' mass aren't precise enough (eg. sampling error greater than an electron's mass).
And more importantly, the transience of the mass in the kilogram. It does have a decay half life, though long, and is subject to electrostatic and photoelectric fluctuations in its electron population, and even migration of whole atoms in/out of the sample. And then there are relativistic differences when the kilogram and the sampler are accelerating relative to each other, which even thermal jiggling can achieve in significance at these tiny mass differences.
Now that we've identified the Higgs boson, we'll learn more about the Higgs field, and learn to measure mass at extremely precise degrees. The "standard" kilograms' measured mass will be seen to fluctuate both over time and among the standard samples by several orders of magnitude (or rather "minitude" ;).
I hope these new quantum experiments at nanoscale (and even femtoscale) give us fundamental measures that count tiny things (including energy cycles) like "electrons per coulomb" from the bottom, rather than statistically survey large things like kilograms and scale down. Both for the more precise and reliable measurements, and to study the tiny deviations among previously believed "identical" particles like electrons. I expect different quantum states of the same particle type will have different masses due to different energy levels among the states. Perhaps we'll establish reliable equivalencies between information and mass, an "E=mc^2" for "joules per iota". And perhaps due to other factors yet undetermined, like perhaps energy in entanglement, or perhaps other "subquantum" effects yet unobserved until our measuring devices are more precise than the variations in their states.
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Picograms per bonghit?
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We can make better displays with this right - now one electron wide pixels!
They should name the unit something related to electricity which takes parts of the picoamperes name so it sounds sort of like it. I've got it! Pikachus!
Yes. and that (16) is the problem.
The amp could be *DEFINED* as 6.24150965Ã--10^18 electrons flowing past a point in one second. At the moment it is measured to be that number of electrons.
Tim.
God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
being able to direct where electrons go could be a huge improvement in efficiency for LEDs. Being able to funnel the electrons directly to the quantum wells built into the p-n junction could result in an output increase of great significance.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Electrons with different quantum states aren't identical. They differ in their quantum states. If the quantum states differ in energy, the difference is hardly negligible:they have different masses.
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