'Accelerator on a chip' demonstrated

Sep 27, 2013
SLAC and Stanford scientists used nanofabricated chips of fused silica just three millimeters long to accelerate electrons at a rate 10 times higher than conventional particle accelerator technology. Credit: Matt Beardsley, SLAC National Accelerator Laboratory

In an advance that could dramatically shrink particle accelerators for science and medicine, researchers used a laser to accelerate electrons at a rate 10 times higher than conventional technology in a nanostructured glass chip smaller than a grain of rice.

The achievement was reported today in Nature by a team including scientists from the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory and Stanford University.

"We still have a number of challenges before this technology becomes practical for real-world use, but eventually it would substantially reduce the size and cost of future high-energy particle colliders for exploring the world of and forces," said Joel England, the SLAC physicist who led the experiments. "It could also help enable compact accelerators and X-ray devices for security scanning, medical therapy and imaging, and research in biology and materials science."

Because it employs commercial lasers and low-cost, mass-production techniques, the researchers believe it will set the stage for new generations of "tabletop" accelerators.

At its full potential, the new "accelerator on a chip" could match the accelerating power of SLAC's 2-mile-long in just 100 feet, and deliver a million more electron pulses per second.

The key to the accelerator chips is tiny, precisely spaced ridges, which cause the iridescence seen in this close-up photo. Credit: Matt Beardsley, SLAC National Accelerator Laboratory

This initial demonstration achieved an acceleration gradient, or amount of energy gained per length, of 300 million electronvolts per meter. That's roughly 10 times the acceleration provided by the current SLAC linear accelerator.

"Our ultimate goal for this structure is 1 billion electronvolts per meter, and we're already one-third of the way in our first experiment," said Stanford Professor Robert Byer, the principal investigator for this research.

Today's accelerators use microwaves to boost the energy of electrons. Researchers have been looking for more economical alternatives, and this new technique, which uses ultrafast lasers to drive the accelerator, is a leading candidate.

Particles are generally accelerated in two stages. First they are boosted to nearly the speed of light. Then any additional acceleration increases their energy, but not their speed; this is the challenging part.

In the accelerator-on-a-chip experiments, electrons are first accelerated to near light-speed in a conventional accelerator. Then they are focused into a tiny, half-micron-high channel within a fused silica just half a millimeter long. The channel had been patterned with precisely spaced nanoscale ridges. Infrared laser light shining on the pattern generates electrical fields that interact with the electrons in the channel to boost their energy. (See the accompanying animation for more detail.)

This video is not supported by your browser at this time.
This animation shows how our accelerator on a chip uses laser light to boost electron energy. In the accelerator-on-a-chip experiments, electrons are first accelerated to near light-speed in a conventional accelerator. Then they are focused into a tiny, half-micron-high channel within a glass chip just half a millimeter long. The channel had been patterned with precisely spaced nanoscale ridges. Infrared laser light shining on the pattern generates electrical fields that interact with the electrons in the channel to boost their energy. Credit: Greg Stewart, SLAC National Accelerator Laboratory

Turning the accelerator on a chip into a full-fledged tabletop will require a more compact way to get the electrons up to speed before they enter the device.

A collaborating research group in Germany, led by Peter Hommelhoff at the Max Planck Institute of Quantum Optics, has been looking for such a solution. It simultaneously reports in Physical Review Letters its success in using a laser to accelerate lower-energy electrons.

Applications for these new would go well beyond particle physics research. Byer said laser accelerators could drive compact X-ray free-electron lasers, comparable to SLAC's Linac Coherent Light Source, that are all-purpose tools for a wide range of research.

Another possible application is small, portable X-ray sources to improve medical care for people injured in combat, as well as provide more affordable medical imaging for hospitals and laboratories. That's one of the goals of the Defense Advanced Research Projects Agency's (DARPA) Advanced X-Ray Integrated Sources (AXiS) program, which partially funded this research. Primary funding for this research is from the DOE's Office of Science.

Explore further: Pinpoint laser heating creates a maelstrom of magnetic nanotextures

More information: E. A. Peralta et al., Nature, 27 Sept 2013 (10.1038/nature12664)
German team's PRL paper available on arXiv: arxiv.org/abs/1308.0464

Related Stories

SLAC scientists create twisted light

Sep 19, 2013

(Phys.org) —Scientists at SLAC have found a new method to create coherent beams of twisted light – light that spirals around a central axis as it travels. It has the potential to generate twisted light ...

Cool electron acceleration

Jun 04, 2013

Physicists from the Max-Planck-Institute of Quantum Optics produced electron pulses from a laser accelerator whose individual particles all have nearly the same, tuneable energy.

Small X-band photoinjector packs powerful punch

Sep 25, 2012

(Phys.org)—Accelerator physicists at SLAC have started commissioning the world's most compact photoinjector – a device that spits out electrons when hit by light. Photoinjectors are used to generate electrons ...

SLAC's newest facility kicks off user run

May 08, 2012

(Phys.org) -- After months of installation and commissioning efforts, SLAC's newest user facility welcomed its first two groups of experimenters on Friday. They came to use the tightly focused electron bunches ...

Recommended for you

Chemically driven micro- and nanomotors

Dec 17, 2014

At least since the movie "The Fantastic Voyage" in 1966, in which a submarine is shrunk down and injected into the blood stream of a human, people have been toying with the idea of sending tiny "micromachines" ...

Pyramid nanoscale antennas beam light up and down

Dec 17, 2014

Researchers from FOM Institute AMOLF and Philips Research have designed and fabricated a new type of nanoscale antenna. The new antennas look like pyramids, rather than the more commonly used straight pillars. ...

User comments : 10

Adjust slider to filter visible comments by rank

Display comments: newest first

El_Nose
5 / 5 (8) Sep 27, 2013
And then comes the explosion of particle research information. I hope this will put particle physics into the realm of the undergrad, and allow more head room for Ph.d students to explore more areas.

I think of this as the equivalent of the classification of all finite abelian groups did for group theory. It pushed finally drew a line in the sand and said -- okay we fully understand this... it's easy now, and they started working on the more difficult.

thats not a great example ...

either way anything that pushes previous graduate level topics fully into the sphere of undergrad learning, pushes fields forward.
antialias_physorg
4.4 / 5 (7) Sep 27, 2013
I hope this will put particle physics into the realm of the undergrad, and allow more head room for Ph.d students to explore more areas.

Check out the roster of people doing work at the LHC. The vast majority are undergrads/PhD students.
(Actually you will find that in most any research institute the people who do the actual research are mostly PhD students. With a ratio of between 1 to 2 postdocs per 10 undergrads)
Q-Star
4.4 / 5 (5) Sep 27, 2013
I hope this will put particle physics into the realm of the undergrad, and allow more head room for Ph.d students to explore more areas.

Check out the roster of people doing work at the LHC. The vast majority are undergrads/PhD students.
(Actually you will find that in most any research institute the people who do the actual research are mostly PhD students. With a ratio of between 1 to 2 postdocs per 10 undergrads)


A tad off topic, but I didn't see anywhere else to post this. I ran across it a couple of days ago. Google Street View has included the LHC in available places for a close up look,,, so in case anyone is interested here's a link that should get ya there,,,

http://www.symmet...d-at-lhc
shavera
5 / 5 (3) Sep 27, 2013
yeah the bulk of scientific research is carried on PhD student backs. What this may do, though, is allow for cheaper smaller accelerators to be present in more locations, reducing cost of doing science.
Lorentz Descartes
1 / 5 (4) Sep 27, 2013
cool research. has anyone read the article and knows what the efficiency of this is? how much of the light's energy is transferred to the electrons?
LordHellFire666
1.8 / 5 (5) Sep 28, 2013
Three words that any Military will love: Particle Beam Weapons
mhenriday
3 / 5 (2) Sep 28, 2013
"Another possible application is small, portable X-ray sources to improve medical care for people injured in combat, ..." I applaud the science - but is it not about time that we started thinking more about eliminating "combat", i e, war, even if not declared by the US Congress, as required by Article I, Section 8 of the US Constitution, than about improving medical for (some of) the injured resulting from the same ?...

Henri
thealternet
1 / 5 (3) Sep 29, 2013
So are they saying the millions of dollars and all the resources spent on the big 2 mile one, is now worthless and obsolete?
El_Nose
5 / 5 (3) Sep 29, 2013
@thealternet

No they are saying that the particle accelerators of the early 20th century now fit on a tabletop, with the hope that they can string these together and make it even more powerful.
reid barnes
1 / 5 (1) Sep 29, 2013
Einstein received the Nobel Prize not for general relativity, but for his work on the photo-electric effect. The video in this article may show a new version of that. Einstein opened a door for quantum theory in connection with the electron and photon. "And your old-school CRT monitor or TV was, technically, a particle accelerator,"said Forbes' Alex Knapp.

Quantum theory assumes Einstein's general theory of relativity, but Einstein challenged quantum theory saying, "God does not play dice." However, in 1964 the Nobel committee chose the relativity quantum road, overlooking flawed non-Euclidean geometry in Einstein's general theory of relativity and overlooking Einstein's views of quantum mechanics. Yet if Einstein was right about general relativity, subsequent scientific developments apparently show his challenges to quantum theory are wrong—IF he was right about general relativity. But what if Einstein was wrong about general relativity, because it is flawed by self-contradicting non-Euclidean geometry, and right about dice?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.