The owners of a wholesale bakery near San Diego must decide whether to offer insurance to their employees or pay into a government fund. Credit: WikipediaAn international team of scientists has discovered a planetary system 1,200 light-years away that hosts two super-Earth-sized planets in its “habitable zone†â€" a region in which conditions are favorable for a planet’s surface to hold liquid water, and potentially life. The discovery was made after meticulous analyses of data from the Kepler telescope, a space observatory that trains its gaze on a wide swath of the sky to identify Earth-sized exoplanets.
Josh Winn, the Class of 1942 Career Development Associate Professor of Physics at MIT, is among the researchers who made the discovery, published this week in the journal Science.
Winn spoke with MIT News about the new planetary system, known as Kepler-62.Q.
What can you tell us about this planetary system? What similarities does it have to our own solar system? A.
This newly discovered system is home to at least five planets, all with sizes comparable to the Earth.
Just as in the solar system, the planets’ orbits are likely to be aligned with one another, like grooves in a record. We are lucky enough from our vantage point on Earth to be viewing that record nearly exactly along its side, and can observe all the planets periodically eclipsing their star as they go around. That’s how the planets were discovered, and their sizes measured: by sensing the small drop in brightness when one of the planets passes in front of the star.
The star is about 30 percent smaller than the sun, and illuminates the planets with less intense, redder starlight.At
the moment, our knowledge is limited to the diameters of the planets and their orbital distances. We don’t know what these planets are made of, although it is plausible that they are mainly rock and iron, similar to the Earth.
We also don’t know what might be in their atmospheres, or on their surfaces.
Astronomers puzzle over a fluorescent glow emanating from Saturn's moon RICHMOND -- Virginia officials reacted with bipartisan dismay on Monday to Defense Department budget shifts that will cost the state thousands of jobs in coming years and will dramatically impact the economies of the Norfolk area and Northern Virginia. The St.
Louis Rams and free agent offensive tackle Jake Long agreed to terms on a deal Sunday night. If the reaction of these Lebanese second division players to a yellow card is anything to go by Alex Ferguson's disgust at Nani's red card in Tuesday's Champions League game was positively angelic President Obama wants a significant jump in education funding to pay for Pell grants for needy college students while also financing his reform agenda for elementary and secondary schools. You don't see Donald Rumsfeld in Washington much anymore.
He made a rare and heartfelt appearance (wearing a sling from recent shoulder surgery) last week at the Pentagon Memorial ceremony, but he increasingly finds himself persona non grata in some corners of D.C. Building owner, factory owner and engineer accused, as death toll in disaster reaches 622The wife of a garment worker killed in the Bangladesh factory collapse has filed a murder complaint against the building's owner, as the death toll from the country's worst industrial disaster climbed to 622.Murder complaints were also filed against the owner of one of the garment firms based in the building and a municipal engineer in the suburb of the capital, Dhaka, where the factory was located.The
owner of the Rana Plaza building, Mohammed Sohel Rana, was arrested after a four-day hunt as he appeared to be trying to flee across the border to India. He is one of nine people being held in connection with the disaster on 24 April, which the government has blamed on the building's faulty and illegal construction.Rana and the others in police custody could face the death penalty if found guilty of murder or mass manslaughter.
None of the accused have commented on accusations that they were to blame.Hundreds of relatives gathered at the site of the disaster on Sunday, some holding up photographs of family members.
A teenage girl broke down in tears when she recognised the body of her mother by her dress after she was brought from the ruins.In all, 53 bodies were recovered on Sunday and rescue workers said they could see more trapped in the rubble.
Authorities were having to use ID cards and mobile phones to identify the dead.Bangladeshguardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds Prime Minister David Cameron announced on Thursday that he would pursue his own proposal for a system of self-regulation after months of inquiries into a phone-hacking scandal.
The couple met at the University of Alabama.
A retrospective at the Portland Museum of Art showcases Lois Dodd, who has reveled for decades in making images of her immediate surroundings. The Democratic-controlled House is poised to give the Pentagon dozens of new ships, planes, helicopters and armored vehicles that Defense Secretary Robert M. Gates says the military does not need to fund next year, acting in many cases in response to defense industry pressures and campaign... Kevin Clash, who left “Sesame Street†after allegations that he had sexual relationships with minors, has already won more than 20 Emmys. • Secret program launched by Bush continued 'until 2011'• Fisa court renewed collection order every 90 days• Current NSA programs still mine US internet metadataThe Obama administration for more than two years permitted the National Security Agency to continue collecting vast amounts of records detailing the email and internet usage of Americans, according to secret documents obtained by the Guardian.The
documents indicate that under the program, launched in 2001, a federal judge sitting on the secret surveillance panel called the Fisa court would approve a bulk collection order for internet metadata "every 90 days". A senior administration official confirmed the program, stating that it ended in 2011.The
collection of these records began under the Bush administration's wide-ranging warrantless surveillance program, collectively known by the NSA codename Stellar Wind.According to a top-secret draft report by the NSA's inspector general â€" published for the first time today by the Guardian â€" the agency began "collection of bulk internet metadata" involving "communications with at least one communicant outside the United States or for which no communicant was known to be a citizen of the United States".Eventually,
the NSA gained authority to "analyze communications metadata associated with United States persons and persons believed to be in the United States", according to a 2007 Justice Department memo, which is marked secret.The Guardian revealed earlier this month that the NSA was collecting the call records of millions of US Verizon customers under a Fisa court order that, it later emerged, is renewed every 90 days.
Similar orders are in place for other phone carriers.The
internet metadata of the sort NSA collected for at least a decade details the accounts to which Americans sent emails and from which they received emails. It also details the internet protocol addresses (IP) used by people inside the United States when sending emails â€" information which can reflect their physical location. It did not include the content of emails."The internet metadata collection program authorized by the Fisa court was discontinued in 2011 for operational and resource reasons and has not been restarted," Shawn Turner, the Obama administration's director of communications for National Intelligence, said in a statement to the Guardian."The program was discontinued by the executive branch as the result of an interagency review," Turner continued. He would not elaborate further.But while that specific program has ended, additional secret NSA documents seen by the Guardian show that some collection of Americans' online records continues today.
In December 2012, for example, the NSA launched one new program allowing it to analyze communications with one end inside the US, leading to a doubling of the amount of data passing through its filters.What
your email metadata revealsThe Obama administration argues that its internal checks on NSA surveillance programs, as well as review by the Fisa court, protect Americans' privacy.
Deputy attorney general James Cole defended the bulk collection of Americans' phone records as outside the scope of the fourth amendment's protections against unreasonable searches and seizures."Toll records, phone records like this, that don't include any content, are not covered by the fourth amendment because people don't have a reasonable expectation of privacy in who they called and when they called," Cole testified to the House intelligence committee on June 18. "That's something you show to the phone company. That's something you show to many, many people within the phone company on a regular basis."But
email metadata is different. Customers' data bills do not itemize online activity by detailing the addresses a customer emailed or the IP addresses from which customer devices accessed the internet.Internal government documents describe how revealing these email records are.
One 2008 document, signed by the US defense secretary and attorney general, states that the collection and subsequent analysis included "the information appearing on the 'to,' 'from' or 'bcc' lines of a standard email or other electronic communication" from Americans.In reality, it is hard to distinguish email metadata from email content. Distinctions that might make sense for telephone conversations and data about those conversations do not always hold for online communications."The calls you make can reveal a lot, but now that so much of our lives are mediated by the internet, your IP [internet protocol] logs are really a real-time map of your brain: what are you reading about, what are you curious about, what personal ad are you responding to (with a dedicated email linked to that specific ad), what online discussions are you participating in, and how often?" said Julian Sanchez of the Cato Institute."Seeing your IP logs â€" and especially feeding them through sophisticated analytic tools â€" is a way of getting inside your head that's in many ways on par with reading your diary," Sanchez added.The
purpose of this internet metadata collection program is detailed in the full classified March 2009 draft report prepared by the NSA's inspector general (IG).One
function of this internet record collection is what is commonly referred to as "data mining", and which the NSA calls "contact chaining".
The agency "analyzed networks with two degrees of separation (two hops) from the target", the report says.
In other words, the NSA studied the online records of people who communicated with people who communicated with targeted individuals.Contact
chaining was considered off-limits inside the NSA before 9/11. In the 1990s, according to the draft IG report, the idea was nixed when the Justice Department "told NSA that the proposal fell within one of the Fisa definitions of electronic surveillance and, therefore, was not permissible when applied to metadata associated with presumed US persons".How the US government came to collect Americans' email recordsThe collection of email metadata on Americans began in late 2001, under a top-secret NSA program started shortly after 9/11, according to the documents. Known as Stellar Wind, the program initially did not rely on the authority of any court â€" and initially restricted the NSA from analyzing records of emails between communicants wholly inside the US."NSA
was authorized to acquire telephony and internet metadata for communications with at least one communicant outside the United States or for which no communicant was known to be a citizen of the United States," the draft report states.George W Bush briefly "discontinued" that bulk internet metadata collection, involving Americans, after a dramatic rebellion in March 2004 by senior figures at the Justice Department and FBI, as the Washington Post first reported.
One of the leaders of that rebellion was deputy attorney general James Comey, whom Barack Obama nominated last week to run the FBI.But Comey's act of defiance did not end the IP metadata collection, the documents reveal. It simply brought it under a newly created legal framework.As soon as the NSA lost the blessing under the president's directive for collecting bulk internet metadata, the NSA IG report reads, "DoJ [the Department of Justice] and NSA immediately began efforts to recreate this authority."The DoJ quickly convinced the Fisa court to authorize ongoing bulk collection of email metadata records. On 14 July 2004, barely two months after Bush stopped the collection, Fisa court chief judge Collen Kollar-Kotelly legally blessed it under a new order â€" the first time the surveillance court exercised its authority over a two-and-a-half-year-old surveillance program.Kollar-Kotelly's order "essentially gave NSA the same authority to collect bulk internet metadata that it had under the PSP [Bush's program], except that it specified the datalinks from which NSA could collect, and it limited the number of people that could access the data".How NSA gained more power to study Americans' online habitsThe Bush email metadata program had restrictions on the scope of the bulk email records the NSA could analyze. Those restrictions are detailed in a legal memorandum written in a 27 November 2007, by assistant attorney general Kenneth Wainstein to his new boss, attorney general Michael Mukasey, who had taken office just a few weeks earlier.The
purpose of that memorandum was to advise Mukasey of the Pentagon's view that these restrictions were excessive, and to obtain permission for the NSA to expand its "contact chains" deeper into Americans' email records. The agency, the memo noted, already had "in its databases a large amount of communications metadata associated with persons in the United States".But, Wainstein continued, "NSA's present practice is to 'stop' when a chain hits a telephone number or [internet] address believed to be used by a United States person."Wainstein told Mukasey that giving NSA broader leeway to study Americans' online habits would give the surveillance agency, ironically, greater visibility into the online habits of foreigners â€" NSA's original mandate."NSA believes that it is over-identifying numbers and addresses that belong to United States persons and that modifying its practice to chain through all telephone numbers and addresses, including those reasonably believed to be used by a United States person," Wainstein wrote, "will yield valuable foreign intelligence information primarily concerning non-United States persons outside the United States."The procedures "would clarify that the National Security Agency (NSA) may analyze communications metadata associated with United States persons and persons believed to be in the United States", Wainstein wrote.In October 2007, Robert Gates, the secretary of defense, signed a set of "Supplemental Procedures" on internet metadata, including what it could do with Americans' data linked in its contact chains. Mukasey affixed his signature to the document in January 2008."NSA will continue to disseminate the results of its contact chaining and other analysis of communications metadata in accordance with current procedures governing the dissemination of information concerning US persons," the document states, without detailing the "current procedures".It was this program that continued for more than two years into the Obama administration.Turner, the director of national intelligence spokesman, did not respond to the Guardian's request for additional details of the metadata program or the reasons why it was stopped. A senior administration official queried by the Washington Post denied that the Obama administration was "using this program" to "collect internet metadata in bulk", but added: "I'm not going to say we're not collecting any internet metadata."NSAUS
national securityThe NSA filesObama administrationFisa courtUnited StatesSurveillanceData protectionPrivacyInternetGeorge BushGlenn GreenwaldSpencer Ackermanguardian.co.uk
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All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds NEW ORLEANS - Director of National Intelligence James R. Clapper Jr.
said Tuesday that he has won a "conceptual agreement" to remove the $53 billion national intelligence budget from Pentagon control and place it under his purview by 2013, as part of an effort to enhance his authority over the U.S....
In his second year as artistic director, Chay Yew has decided to put on three productions, instead of the usual five, as part of a strategic plan to shore up the theater’s shaky finances. 'We don't believe that you should have to pinkify something to make it acceptable for girls,' says Alice TaylorFor many people, 3D printing is still a thing of science fiction. Less a tangible technology and more a reason to shout "They're printing 3D guns now? Endtimes! ENDTIMES!", slap on some tin-foil and run for the nearest bunker.Yet
there are people building businesses out of this, which although innovative, disruptive and all those other words you have to use in these cases, are also proper, down-to-earth businesses.MakieLab is one of them. Based in London, the company raised its first seed funding in August 2011 to work on prototype 3D-printed dolls â€" Makies â€" which customers would be able to design themselves on its website.That
site launched in alpha in May 2012, the company raised $1.4m from early-stage investors in June that year, and now in March 2013 MakieLab has released an iPad app called Makies Doll Factory to help people make and order Makies from their tablet."We started with the question of whether virtual goods could produce physical goods," explains co-founder and CEO Alice Taylor. "Would 3D printing mean we could make virtual crates and barrels into real crates and barrels? The short answer was yes, but nobody was going to buy a crate or a barrel…"Hence dolls, based on Taylor and her three co-founders' love of online avatars, and also the fact that dolls were the biggest category in the toys market â€" and a blissful lack of awareness about how difficult they'd be for a 3D-printing startup."An
eminent industry figure said to me a year in 'You do realise that was the hardest choice to make, don't you?'," laughs Taylor.
"YES I DO NOW, thank you very much. But we've done it!"Rooting for the underdogNot that MakieLab is a dolls company: Taylor says it's more of a software manufacturing platform that can output 3D-printed shapes, including dolls but in the future other kinds of products."The dolls are product number one, but we want to produce toys and games â€" or toy/game combos â€" that are really carefully targeted towards specific consumer groups," she says.
"Makies are for girls aged 8+, but our second product may be for boys.
Not that girls won't want to play with it too, or boys with Makies."When MakieLab raised its $1.4m
of early-stage funding, there was a notable outpouring of warmth from fellow startups. That's partly because the four co-founders were well-connected in the London startups scene and beyond, but Taylor thinks there were other reasons."I think part of it came from people seeing a company doing something frankly quite weird, new and very experimental, with two women and two men in the four founders, at a time when people tended to picture startups as being three skinny guys from Stanford," says Taylor."So it was partly people going 'Wow! Underdog, that's amazing', and partly seeing it as encouraging anyone else who's got interesting new ideas, sees those skinny Stanford boys and thinks 'I'm never going to get into this startup scene'. And of course, you can."Makies may have initially launched as a website, but mobile was in mind from the start. MakieLab used the Unity game engine to ensure its making tools would transfer elegantly to mobile devices â€" something that also means porting the new iPad app to Android will happen sooner rather than later.In the two days since the iPad app was released, people have made more than 4,500 Makies with it â€" created them in the app, if not actually paid for real versions.
Taylor says that already, iPad users are more "much more engaged" than website visitors in their usage of the creation tools.Mobile game plansMakieLab is already working on a separate Makies-themed mobile game to be released this summer, which will be selling digital goods rather than physical dolls. Taylor says that the company is thinking hard about how this will work though, to ensure parents are comfortable with whatever in-app purchase model is used."The game will be similar to the app, in that you're creating characters in a maker-space, but that space will now expand a bit, and you'll be able to make things other than just the character. You'll be making clothes and accessories, and harvesting materials to make them," says Taylor.Something
that I like about MakieLab both as a geek-journalist and a parent is the way it encompasses both digital and physical play: virtual and real dolls. This blending of digital and physical play seems like an important trend, especially if you watch how children seamlessly move between the two worlds given the chance.It's
a view not shared by some commenters when I've written about children's apps on this blog, who grouch that kids should be playing outside with physical toys, not using apps on touchscreens â€" as if this is an either/or choice."Exactly! It's not either/or: kids will do both," says Taylor. "They'll play on-screen, then go outside and play with their friends, and often the screen will be in their pocket while they're playing with their friends, or their friends will be with them when they're playing on-screen.
This is all just blended now."This
debate was actually the spark that created MakieLab back in 2010, when Taylor was at a digital conference in New York that was co-located with a toy fair â€" with some crossover in delegates between the two.As
one of the digital speakers was taking questions, someone from the toy industry asked "All this screen business is all very well, but don't you want kids to go outside and play with a hoopla stick?"As this question rattled around her head, Taylor wandered the toy fair, and realised how completely separate the toy and digital entertainment industries were."It was all plastic products made far away in China, completely separate from the content creation happening there in America," she says. "It just felt so weird. How could we make it blend better?"Digital loves physicalThis isn't to say people who work almost exclusively in digital entertainment don't love a good toy. In fact, something I've noticed a lot is that people I met who spend their days subsumed in digital content often have sprawling vinyl, book or toy collections at home.Taylor has noticed it too. "I think it's a symptom!" she says, noting that people who are heavily involved in digital may have a heightened sense of how intangible it is."I
started making websites in 1994, but now I basically can't see any of my work from then through to around 2003. It's been rewritten, archived or gone offline and disappeared," she says. "Digital people feel that in their bones: we know that if we don't take screenshots and make photographs of them to frame and hang on the wall, we can't guarantee anyone will see this in the future. And of course, we all love toys.
Toys are amazing."Well, some toys.
Another interesting thing about Makies and 3D-printed toys more generally is their removal of gender barriers. Boys can make girl dolls, girls can make boys, and (with apologies to Blur) they can come up with something they really love without worrying whether the box is pink or khaki.That's
not quite the case in the traditional toy industry.
Taylor laughs heartily while telling me about Hasbro's plan to make Nerf appeal to girls by making a pink crossbow called the Nerf Rebelle Heartbreaker, for example."It takes a brave parent to walk down the boys aisle in a shop to buy a giant gun for their daughter, or walk down the girls aisle to buy their son a doll.
It basically doesn't happen. Your radical lefty Guardian reader, yes, but for the most part no," says Taylor."We
don't as a company believe that you should have to pinkify something to make it acceptable for girls, or khakify it for boys.
We don't want to start saying 'You're a boy, you can't put a skirt on that doll'.
Whoever the kid is, they should be able to make boy and girl dolls."3D-printing disruptionMakieLab isn't just trying to disrupt the traditional toy industry on gender lines, of course.
3D printing itself could be seen as a big threat to those aisles full of toys, although also a big opportunity if their manufacturers embrace it.Has
the toy industry been sniffing around MakieLab? "Strangely, I don't know if they've noticed us yet," says Taylor."They haven't been in touch. The games industry has, journalists, trade shows, museums and even a makeup company has been in touch, but no toy companies yet. I don't know if it's on their radar, although of course it could be, and they might be plotting to kill us right now! We haven't heard from them."She goes on to stress that of course 3D printing is on the toy companies' radar â€" for their own internal prototyping processes if nothing else â€" and predicts that in 5-10 years most manufacturers will be using it commercially.
But there are barriers."The question is whether as businesses they are prepared yet to start to look at it for production.
It's expensive compared to stuff made in China, and political too if you're a giant company who's been manufacturing out there for 15 years," she says."It's
where all your people, machines, systems and logistics are, and it's the world you understand.
So when some upstart comes along and says you should be 3D-printing in London now… I suspect that is the barrier. There will be plenty of emerging-tech types in toy companies saying this is part of the future, but as a big company it takes a long time to change course."The
local-manufacturing point is potentially important. MakieLab currently makes its dolls in London and Amsterdam, with ambitions to widen its manufacturing network as more 3D-printing facilities become available in the years ahead.That's why Makies are expensive compared to more-famous doll brands â€" they start at £59.99 for a basic model, with the skin colours, clothing and accessories costing extra. Explaining the difference is a political discussion, by necessity."We like our cheap goods, yet at the same time, we have these cheap goods because there are people in China who'll work for 20 dollars a week," says Taylor.
"Everybody knows that is fucked up, and it will change. The minimum wage went up 20% last year in China, and it will go up again."Distributed networksMakieLab's hope is that when the placement of 3D-printing facilities around the world is evenly distributed, production will be easier for the company and others like it.Taylor
also makes an interesting parallel with this future manufacturing network: "It'll make a distributed network of manufacturing machines, and that's how the internet started: it was a distributed network," she says. "That's amazing, but we're not there yet with 3D printing."Hence
the £59.99 starting price for a Makie doll, which Taylor says leaves "very small margins" for MakieLab, although she hopes to improve them over time as the business scales up â€" ultimately bringing the price including extras under £50, and ideally under £40."It's an inevitability that prices will come down, but how fast? Nobody really knows," she says. "That's very exciting, but that's also what keeps me up every night at 3am. I could do with slightly less excitement, thank you very much! But it is amazing being in this mix of industries, where every month there's a new development."Is 3D printing heading for a fall though? There's such a lot of hype and noise around it at the moment, and that whiff of science fiction â€" I write this as someone who loves the genre â€" that may be provoking an exaggerated backlash from sceptics, and inflated expectations from supporters.Taylor quotes Gartner's famous hype cycle theory for emerging technologies. "3D printing is right at the top of the peak of inflated expectations, before the trough of disillusionment," she says."For
some people, the trough will be 'Why can't I print my own kidneys?', and it's going to be a really big trough for people who are thinking that we're going to start 3D-printing houses on the moon next week. But for us, it will be something like 'Why isn't the price coming down as fast as we thought it would?'.
And then the price will come down."3D printingAppsiPadTablet computersMobile phonesSmartphonesToysTechnology startupsStuart Dredgeguardian.co.uk
© 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds The end of the D.C.
telephone weather line is just another example of the contempt the young show for the old. Landslides triggered by heavy rains killed at least 24 people in the mountains above Rio de Janeiro and prompted Brazilian President Dilma Rousseff to call for tougher action to eradicate precarious dwellings.
Nineteen bombs and an assassination on Tuesday served as a reminder of the violence that regularly afflicts Iraq a decade after the American-led invasion.
The bride is an associate professor at Rutgers; the groom is a professor at Columbia. A new approach that allows objects to become “invisible†has now been applied to an entirely different area: letting particles “hide†from passing electrons, which could lead to more efficient thermoelectric devices and new kinds of electronics.The concept â€" developed by MIT graduate student Bolin Liao, former postdoc Mona Zebarjadi (now an assistant professor at Rutgers University), research scientist Keivan Esfarjani, and mechanical engineering professor Gang Chen â€" is described in a paper in the journal Physical Review Letters.Normally,
electrons travel through a material in a way that is similar to the motion of electromagnetic waves, including light; their behavior can be described by wave equations.
That led the MIT researchers to the idea of harnessing the cloaking mechanisms developed to shield objects from view â€" but applying it to the movement of electrons, which is key to electronic and thermoelectric devices.Previous work on cloaking objects from view has relied on so-called metamaterials made of artificial materials with unusual properties. The composite structures used for cloaking cause light beams to bend around an object and then meet on the other side, resuming their original path â€" making the object appear invisible. “We were inspired by this idea,†says Chen, the Carl Richard Soderberg Professor of Power Engineering at MIT, who decided to study how it might apply to electrons instead of light. But in the new electron-cloaking material developed by Chen and his colleagues, the process is slightly different. The MIT researchers modeled nanoparticles with a core of one material and a shell of another. But in this case, rather than bending around the object, the electrons do actually pass through the particles: Their paths are bent first one way, then back again, so they return to the same trajectory they began with.In computer simulations, the concept appears to work, Liao says.
Now, the team will try to build actual devices to see whether they perform as expected. “This was a first step, a theoretical proposal,†Liao says. “We want to carry on further research on how to make some real devices out of this strategy.â€While
the initial concept was developed using particles embedded in a normal semiconductor substrate, the MIT researchers would like to see if the results can be replicated with other materials, such as two-dimensional sheets of graphene, which might offer interesting additional properties.The MIT researchers’ initial impetus was to optimize the materials used in thermoelectric devices, which produce an electrical current from a temperature gradient. Such devices require a combination of characteristics that are hard to obtain: high electrical conductivity (so the generated current can flow freely), but low thermal conductivity (to maintain a temperature gradient). But the two types of conductivity tend to coexist, so few materials offer these contradictory characteristics. The team’s simulations show this electron-cloaking material could meet these requirements unusually well.The simulations used particles a few nanometers in size, matching the wavelength of flowing electrons and improving the flow of electrons at particular energy levels by orders of magnitude compared to traditional doping strategies. This might lead to more efficient filters or sensors, the researchers say.
As the components on computer chips get smaller, Chen says, “we have to come up with strategies to control electron transport,†and this might be one useful approach.The
concept could also lead to a new kind of switches for electronic devices, Chen says. The switch could operate by toggling between transparent and opaque to electrons, thus turning a flow of them on and off. “We’re really just at the beginning,†he says. “We’re not sure how far this is going to go yet, but there is some potential†for significant applications.Xiang
Zhang, a professor of mechanical engineering at the University of California at Berkeley who was not involved in this research, says “this is very exciting work†that expands the concept of cloaking to the domain of electrons.
The authors, he says, “uncovered a very interesting approach that may be very useful to thermoelectric applications.â€This research was funded by the U.S.
Department of Energy (DOE) through MIT’s Solid-State Solar-Thermal Energy Conversion center, a DOE Energy Frontier Research