https://www.fau.eu/2017/09/25/news/research/the-fastest-light-driven-current-source/
Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.
[...] For their experiments, the scientists fired extremely short laser pulses with specially engineered waveforms onto graphene. When these light waves hit the graphene, the electrons inside were hurled in one direction, like a whiplash. 'Under intense optical fields, a current was generated within a fraction of an optical cycle – a half femtosecond. It was surprising that despite these enormous forces, quantum mechanics still plays a key role,' explains Dr. Takuya Higuchi from the Chair of Laser Physics, the first author of the publication.
Light-field-driven currents in graphene (DOI: 10.1038/nature23900) (DX)
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Scientists have used the tip of a scanning tunnelling microscope to manipulate electrons in graphene, potentially making the material usable for more applications:
Graphene – a one-atom-thick layer of the stuff in pencils – is a better conductor than copper and is very promising for electronic devices, but with one catch: Electrons that move through it can't be stopped.
Until now, that is. Scientists at Rutgers University-New Brunswick have learned how to tame the unruly electrons in graphene, paving the way for the ultra-fast transport of electrons with low loss of energy in novel systems. Their study was published online in Nature Nanotechnology [DOI: 10.1038/nnano.2017.181] [DX].
[...] [Eva Y. Andrei's] team managed to tame these wild electrons by sending voltage through a high-tech microscope with an extremely sharp tip, also the size of one atom. They created what resembles an optical system by sending voltage through a scanning tunneling microscope, which offers 3-D views of surfaces at the atomic scale. The microscope's sharp tip creates a force field that traps electrons in graphene or modifies their trajectories, similar to the effect a lens has on light rays. Electrons can easily be trapped and released, providing an efficient on-off switching mechanism, according to Andrei.
Related: Electrons Controlled in Graphene on a Sub-Femtosecond Scale Using Lasers
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @04:43PM (3 children)
Is this applicable to quantum computing? Quantum computing has been getting a lot of attention lately as AI becomes more important, and as Microsoft is working on a quantum computing programming language [soylentnews.org].
(Score: 2) by c0lo on Wednesday September 27 2017, @05:15PM (1 child)
Yes, it's not!
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @05:19PM
LOL! That's funny and not funny at the same time! LOL! LOL!
(Score: 2) by stormwyrm on Wednesday September 27 2017, @11:50PM
Numquam ponenda est pluralitas sine necessitate.
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @04:49PM (8 children)
Terahertz computing will really be something else when we finally achieve it. Based on what's being researched here, getting into the femtosecond range means it's becoming more and more feasible. While I think it could take a long time, perhaps even decades, to see this manifest itself in full x64 implementations, we could very well see it used in simpler RISC designs well before then.
Then again, Moore's Law often surprises us. That which seems unlikely becomes that which is real so quickly.
Just think, even a bare minimum 1 THz single-core processor could potentially do the same computation as 300 times 3 GHz processors could!
(Score: 2) by ledow on Wednesday September 27 2017, @05:08PM (7 children)
The problem is not speed, but distance.
These things are constrained by the speed of light. The reason chips can't go faster at the moment is because - at the speed of light - it starts to take longer than a clock cycle for a signal to traverse the chip. Modern chips rely on a common clock across the chip.
And when you make the chips small enough to traverse in the time you need, the distance again comes into place, as the current leaks through things you don't want it to on that fine a scale, and generates a lot of heat in a tiny area.
The problem of THz computing isn't being able to trigger a fast light impulse. It's being able to do anything useful with that light impulse if you want it to pass through billions of "gates" etc. along the way and get an answer out the other end that's correct, consistent, and timed properly.
Though this is useful in all kinds of context, THz computing is deca-years ago. We've stagnated at about 3-4GHz in home computers for a reason. And even the fastest chips are only 8-9GHz.
(Score: 1, Interesting) by Anonymous Coward on Wednesday September 27 2017, @05:15PM (1 child)
Removing the need for a monotonic clock pulse could very well be one of the benefits of this technology. While clockless traditional CPU designs do exist, they haven't gotten transistor switching time down to the half femtosecond like is being described here. Combine this with RISC architectures that reduce the number of transistors needed to being with and we really start to see some real potential with this kind of technology.
(Score: 2) by ledow on Thursday September 28 2017, @07:38AM
But removing the need for a monotonic clock pulse could also be done WITHOUT this technology.
Even at traditional transistor speed, they can't manage to match clocked chips.
It may also mean a complete change of architecture and many even programming paradigm (i.e. everything suddenly becomes asynchronous).
But it doesn't need THz transistors to get there.
(Score: 2) by c0lo on Wednesday September 27 2017, @05:22PM (2 children)
You may want to recheck your calculations. 1THz => 1 femto-light-second = 3 m
It's not the travel space that causes the processing delay, it's the maximum switching speed of the transistor gates forming/maintaining/modifying the signal.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 1, Informative) by Anonymous Coward on Wednesday September 27 2017, @05:44PM (1 child)
"tera" is 1012. "femto" is 10−15. You want to be using "pico", 10−12, to keep your bases consistent.
A 1 THz wavelength is 1 pico light-second which is 0.003 m which is 3 mm. It's tiny.
(Score: 2) by c0lo on Wednesday September 27 2017, @06:10PM
Yeap, my mistake.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by takyon on Wednesday September 27 2017, @05:26PM
Just increase the core count to hundreds or thousands.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Grishnakh on Wednesday September 27 2017, @10:29PM
The reason chips can't go faster at the moment is because - at the speed of light - it starts to take longer than a clock cycle for a signal to traverse the chip. Modern chips rely on a common clock across the chip.
Right. The way to deal with this is to put the CPU in a small subspace field so that the speed of light is faster.
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @04:52PM (5 children)
If I get a computer with one of these chips will it finally let me run Firefox at a reasonable speed?
(Score: 2) by c0lo on Wednesday September 27 2017, @05:24PM
Yes, but only until the next release
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by Grishnakh on Wednesday September 27 2017, @05:47PM (3 children)
Sure. It might even let you run Chrome at a reasonable speed, since Chrome is so much slower than Firefox (unless you have unlimited memory perhaps).
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @05:53PM (1 child)
I've been using the Firefox 57 beta and it's damn slow for me compared to Chrome on the same system. I know it's not my Firefox extensions that are to blame, because Firefox 57 doesn't fucking support the extensions I was using!
(Score: 2) by Grishnakh on Wednesday September 27 2017, @10:28PM
Try this test: open up 100 tabs to different sites, in both browsers. Now see which one crawls.
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @06:35PM
Troll post is obvious. You are either trolling, or trolling. Can't be both.
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @04:56PM (6 children)
Why is it surprising? Quantum mechanics govern all aspects of physicality, big or very small. Why wouldn't they be involved in this case, too?
(Score: 2) by c0lo on Wednesday September 27 2017, @05:28PM (4 children)
Or so they like you to think.
In reality, it is the lizard people that controls the physicality and (for now) the Illuminati the ones that control your mind.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @06:02PM (3 children)
Can you please keep your alt-right "lizard people" and "Illuminati" drivel contained to Slashdot?
We're trying to have an intelligent discussion here about cutting-edge microprocessor technologies. You're welcome to contribute something useful if you're capable of doing so, but otherwise please don't gum up this place with alt-right nonsense.
(Score: 2) by c0lo on Wednesday September 27 2017, @06:16PM
(Perhaps some innocent fresh-meat got lost from the green-site into here?
Just in case... don't scare him, boys. Not yet.
trollish grin)
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by Azuma Hazuki on Wednesday September 27 2017, @07:25PM
c0lo, if I'm reading him(?) right, is being ironic. As far as I know there's only one person who seems to seriously think there are actual lizard people, and she's...nutty. For a lot of reasons.
I am "that girl" your mother warned you about...
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @07:41PM
This site already has plenty of alt-right nonsense and trolls, c0l0's is pretty tame by the daily standards here.
(Score: 0) by Anonymous Coward on Wednesday September 27 2017, @11:42PM