Advancing secure communications: A better single-photon emitter for quantum cryptography

Advancing secure communications: A better single-photon emitter for quantum cryptography

Wednesday, April 10, 2013

In a development that could make the advanced form of secure communications known as quantum cryptography more practical, University of Michigan researchers have demonstrated a simpler, more efficient single-photon emitter that can be made using traditional semiconductor processing techniques.

Single-photon emitters release one particle of light, or photon, at a time, as opposed to devices like lasers that release a stream of them. Single-photon emitters are essential for quantum cryptography, which keeps secrets safe by taking advantage of the so-called observer effect: The very act of an eavesdropper listening in jumbles the message. This is because in the quantum realm, observing a system always changes it.

For quantum cryptography to work, it's necessary to encode the message?which could be a bank password or a piece of military intelligence, for example?just one photon at a time. That way, the sender and the recipient will know whether anyone has tampered with the message.

While the U-M researchers didn't make the first single-photon emitter, they say their new device improves upon the current technology and is much easier to make.

"This thing is very, very simple. It is all based on silicon," said Pallab Bhattacharya, the Charles M. Vest Distinguished University Professor of Electrical Engineering and Computer Science, and the James R. Mellor Professor of Engineering.

Bhattacharya, who leads this project, is a co-author of a paper on the work published in Nature Communications on April 9.

Bhattacharya's emitter is a single nanowire made of gallium nitride with a very small region of indium gallium nitride that behaves as a quantum dot. A quantum dot is a nanostructure that can generate a bit of information. In the binary code of conventional computers, a bit is a 0 or a 1. A quantum bit can be either or both at the same time.

The semiconducting materials the new emitter is made of are commonly used in LEDs and solar cells. The researchers grew the nanowires on a wafer of silicon. Because their technique is silicon-based, the infrastructure to manufacture the emitters on a larger scale already exists. Silicon is the basis of modern electronics.

"This is a big step in that it produces the pathway to realizing a practical electrically injected single-photon emitter," Bhattacharya said.

Key enablers of the new technology are size and compactness.

"By making the diameter of the nanowire very small and by altering the composition over a very small section of it, a quantum dot is realized," Bhattacharya said. "The quantum dot emits single-photons upon electrical excitation."

The U-M emitter is fueled by electricity, rather than light?another aspect that makes it more practical. And each photon it emits possesses the same degree of linear polarization. Polarization refers to the orientation of the electric field of a beam of light. Most other single-photon emitters release light particles with a random polarization.

"So half might have one polarization and the other half might have the other," Bhattacharya said. "So in cryptic message, if you want to code them, you would only be able to use 50 percent of the photons. With our device, you could use almost all of them."

This device operates at cold temperatures, but the researchers are working on one that operates closer to room temperature.

The paper is titled "Electrically-driven polarized single-photon emission from an InGaN quantum dot in a GaN nanowire." The first author is Saniya Deshpande, a graduate student in electrical engineering and computer science. The work is supported by the National Science Foundation. The device was fabricated at the U-M Lurie Nanofabrication Facility.

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University of Michigan: http://www.umich.edu/

Thanks to University of Michigan for this article.

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Source: http://www.labspaces.net/127675/Advancing_secure_communications__A_better_single_photon_emitter_for_quantum_cryptography

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Key senators reach deal on background checks for gun buyers

By Richard Cowan

WASHINGTON (Reuters) - Prospects for a gun control bill's passage in the Senate in coming weeks got a boost on Wednesday with a bipartisan agreement on background checks for gun buyers.

Democratic Senator Joe Manchin of West Virginia and Republican Senator Pat Toomey of Pennsylvania brokered the deal and were scheduled to announce it during a news conference at 11 a.m. EDT (1500 GMT) Wednesday.

According to a Senate Democratic aide, the measure would expand criminal background checks for prospective gun buyers to include sales made at gun shows and online.

Sales among friends or family members would be exempt from the requirement, which is designed to close many loopholes. Analysts have said as many as 40 percent of gun buyers have been able to avoid background checks under the current system.

The proposal for expanded background checks - which includes a requirement for sellers to keep records of sales - appears to be Obama's best hope for meaningful gun control legislation in the wake of the December massacre of 20 children and six adults at a school in Newtown, Connecticut.

Several family members of victims from the shootings at Sandy Hook Elementary School in Newtown are in Washington this week to help Obama's team pressure lawmakers for action.

More controversial parts of the president's plan - such as a ban on rapid-firing "assault" weapons like the one used in Connecticut and limits on the capacity of ammunition magazines - appear to have a slim chance of clearing the U.S. Senate, which is led by Obama's Democrats. Such measures face an even tougher road in the Republican-controlled House of Representatives.

Manchin's participation in the deal on background checks is widely seen as boosting the prospects for the legislation's passage. The freshman senator represents a state where gun ownership has long been passionately protected and where attempts to regulate guns have been strongly opposed.

On Thursday, the Senate is scheduled to hold its first test vote on a gun control bill.

More than a dozen conservative Republican senators have threatened a filibuster aimed at delaying consideration of any gun restrictions. But other Republicans - many acknowledging public opinion polls that have shown that more than 80 percent of Americans favor expanded background checks - have said Obama's proposals should get a floor vote in the Senate. Senate Leader Harry Reid, the Nevada Democrat who schedules votes in the chamber, has echoed that position.

The measure likely to pass the Senate, expected to include expanded background checks, more funding for school security and tighter restrictions on gun trafficking, falls far short of what Obama had pressed for. But it is more extensive than what the influential National Rifle Association, the nation's largest gun rights group, has warned that it would accept.

Whatever gun control measures clear the Senate, they are likely to face a more challenging path in the House, where many Republicans have vowed to oppose any gun restrictions.

(Editing by David Lindsey and Lisa Von Ahn)

Source: http://news.yahoo.com/senate-cast-first-gun-control-votes-thursday-025348479.html

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Dutch uncover large-scale meat fraud

10 April 2013 Last updated at 15:42 ET

Some 50,000 tonnes of meat supplied by two Dutch trading companies and sold as beef across Europe since January 2011 may have contained horsemeat.

The meat is being recalled where possible, the Dutch authorities say.

There was no evidence that the meat was a threat to human health, the Netherlands Food and Consumer Product Safety Authority said.

In total, 132 companies in the Netherlands and some 370 more around Europe are affected by the discovery.

The suspect meat was supplied by Wiljo Import en Export BV and Vleesgroothandel Willy Selten.

The two companies are owned by one man who has already previously been investigated by food safety officials, the BBC's Matthew Price reports.

The latest find was made as part of EU-wide tests to trace horse DNA in processed beef foods and to detect a veterinary drug used on horses.

The results of the rest of the tests conducted across the EU will be made public next week - giving consumers a better idea of how widespread the scandal has been.

The Dutch decided to release their results early because of the magnitude of what they had discovered, our correspondent says.

'Already consumed'

The recall covers meat dating back to 1 January 2011 up until 15 February this year, the Dutch food authority said on Wednesday.

Continue reading the main story

Analysis

With its imposing grey gates, the Willy Selten factory in Oss does not receive many visitors outside the meat trade. That was according to the owner, whom we met on a chilly Saturday afternoon in February. Investigations into the Netherlands' role in the Europe-wide horsemeat scandal had brought us here.

The suspicion is now that it was here, behind the corrugated shutters, that horsemeat was relabelled and sold on as beef. The Dutch Food Safety Authority offered Willy Selten an ultimatum: "Trace the origins of your meat or we will take over."

On Wednesday morning an urgent recall message was sent out to 502 companies across Europe - a "rapid alert" to locate all of the products that may have been contaminated. Willy Selten has been under strict supervision ever since the initial suspicions emerged in February.

It may be a surprise to many to learn that the factory is still operating, though reports in the Dutch media claim it is facing bankruptcy. A Food Safety Authority spokeswoman explained: "Our policy in the Netherlands is that everybody should be given a second chance."

Due to the lapse of time, a lot of the meat "may already have been consumed", it added.

Inspectors examining the records of the Dutch trading companies found that the origin of the supplied meat was unclear. As a result it was not possible to confirm whether slaughterhouses had respected procedures.

Some of the suspect meat was also exported to Germany, France and Spain, where authorities have been alerted. The British Food Standards Agency has confirmed that a small number of UK companies may have received products from the Dutch wholesalers.

"It might contain traces of horsemeat, but we don't know for certain at the moment if this is the case," said Esther Filon, a spokeswoman for the Dutch food authority.

"The buyers have probably already processed the meat and sold it on. They, in turn, are obliged to inform their own customers."

New EU law

All EU member states have been informed of the Dutch discovery, EU spokesman Frederic Vincent told the BBC.

They have been urged to check whether or not processed meat products coming from the plants in question were still on the market, he added.

"The Dutch announcement is a consequence of the investigations which were launched by EU member states a few weeks ago," the EU spokesman said.

"Given the size of the fraud, the Dutch decided to go public with their discovery."

Traces of horsemeat have been found in numerous processed beef frozen meals across Europe.

In February, Dutch officials raided a meat processing plant suspected of mislabelling beef and ordered the withdrawal of suspicious products from supermarket shelves.

Other countries affected included the UK, the Republic of Ireland, France, Switzerland, Sweden and Germany.

The EU is set to adopt an Animal and Plant Health legislative proposal in the coming weeks, which includes clauses designed to tackle food fraud.

Source: http://www.bbc.co.uk/news/world-europe-22098763#sa-ns_mchannel=rss&ns_source=PublicRSS20-sa

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Arkansas Senate passes unemployment drug testing bill

By Suzi Parker

LITTLE ROCK, Ark (Reuters) - The Republican-led Arkansas state Senate approved a measure on Monday that would require random drug testing of Arkansas residents who receive state unemployment benefits - a plan that the state's Democratic governor said could violate federal law.

The bill, which passed on a 25-5 vote and now goes to a House committee, could affect about 85,000 Arkansas residents currently receiving unemployment benefits.

If the measure becomes law, those seeking unemployment benefits would have to sign a waiver and allow for random drug testing. Those who refuse to sign or who test positive for drugs would not be entitled to benefits.

Some other states have adopted measures making a person discharged from work for failing an employer's drug test on the job ineligible to collect employment benefits, according to the National Conference of State Legislatures.

In Texas, Governor Rick Perry has a proposal in that state's legislature that would require drug tests for both unemployment and welfare recipients. But it has not yet passed a chamber.

The Arkansas bill's sponsor, Republican state Senator Jeremy Hutchinson, said that his measure was "more of an enforcement mechanism than anything else."

"Arkansas law states that you have to be adequately seeking employment, and by that you have to pass a drug test since so many employers require drug tests," Hutchinson said.

He said that 80 percent of the state's employers require a drug test. The unemployment testing, Hutchinson said, would cost the state less than $30,000 a year to administer.

Rita Sklar, director of the American Civil Liberties Union of Arkansas, said the group plans to fight the measure if it becomes law. Governor Mike Beebe, a Democrat, also has issues with the bill.

"We have concerns about whether the bill will put us in violation of the federal unemployment laws administered by the U.S. Department of Labor," said Matt DeCample, Beebe's spokesman. "There are also continued concerns as to whether the cost of implementing such a program would produce any real savings in offset."

(Reporting by Suzi Parker; Editing by Mary Wisniewski, Cynthia Johnston and Vicki Allen)

Source: http://news.yahoo.com/arkansas-senate-passes-unemployment-drug-testing-bill-011921110.html

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UK-Odd Summary

Teenager in waste bin crushed by Luxembourg rubbish truck

BRUSSELS (Reuters) - A French teenager who had hidden inside a waste bin was crushed to death inside a rubbish collection truck in Luxembourg on Saturday, police said. Refuse men only discovered the 17-year-old when he shouted out as they emptied the bin into the back of the lorry early on Saturday morning, but by then he was already in the grasp of the crushing mechanism.

Rooftop beehives create buzz above French parliament

PARIS (Reuters) - The roof of France's National Assembly is ready to buzz with activity after the arrival of three large bee hives this week as part of a project to promote pesticide-free honey. The bees are expected to be moved in once the weather warms up, should produce up to 150 kg of honey a year and help pollinate flowering plants around the capital at a time of worldwide decline in bee numbers.

Spain raises minimum age for marriage and sex

MADRID (Reuters) - Spain has raised the minimum age for marriage to 16 from what had been one of the lowest in the world at 14 as part of a wider reform to improve health and safety for children and adolescents. The reform, announced by Spanish Health Minister Ana Mato on Friday, also raises the age for consensual sex from what was the lowest in Europe at 13. The new age will be decided by Parliament.

Popstar Justin Bieber given month to collect pet monkey

BERLIN (Reuters) - Teenage pop sensation Justin Bieber has been given a month to provide German authorities with the papers they need to release his pet monkey "Mally". Customs officials seized Bieber's capuchin monkey at Munich Airport last week when the 19-year-old failed to present the health and species protection certificates required to bring the pet into the country.

Arizona "pregnant man" to appeal ruling rejecting divorce

PHOENIX (Reuters) - A transgender man who made worldwide headlines after he married and gave birth to three children will appeal an Arizona judge's ruling denying him a divorce from his wife of 10 years, his attorneys said on Tuesday. Thomas Beatie, 39, was born a woman but began living as a man in his 20s, initiating hormone treatments, undergoing breast-removal surgery and legally changing his name, though he kept his female reproductive organs.

Samoan airline says pay by weight plan "fairest" way to fly

SYDNEY (Reuters) - A Samoan airline that says it is the world's first carrier to charge passengers by their weight rather than per seat defends the plan as the fairest way to fly, in some cases actually ending up cheaper than conventional tickets. Samoa Air, which opened in 2012, asks passengers to declare their personal weight during booking, which is then charged per kilogram (2.2 lb) at a rate dependent on flight length. The customers will also be weighed at the check-in counter.

Trump withdraws "orangutan" lawsuit against comic Bill Maher

NEW YORK (Reuters) - Donald Trump is withdrawing his lawsuit against television host and comedian Bill Maher seeking $5 million (3.3 million pounds) that Maher said he would give to charity, in a seemingly facetious offer, if Trump could prove he was not the son of an orangutan. The lawsuit stems from comments Maher made during an appearance on NBC's "The Tonight Show" in January in which he said an orangutan's fur was the only thing in nature that matches the shade of Trump's trademark hair.

Waist-deep in mud, Cameron rescues distressed sheep

LONDON (Reuters) - Bogged down by a stagnating economy and sinking poll ratings, British Prime Minister David Cameron ventured into a new swamp when he waded waist-deep into mud to rescue a drowning sheep. Cameron was on his way back from visiting a farmer near his weekend home in the Oxfordshire countryside last month when he heard bleating and spotted a ewe that had got stuck in the mud after following her two lambs.

Two inmates flee Texas jail, possibly only in underwear

SAN ANTONIO, Texas (Reuters) - An inmate suspected of strangling a man with shoelaces escaped with a fellow prisoner from a Texas jail on Tuesday, triggering a manhunt for what authorities described as two dangerous fugitives, possibly clad in nothing but their underwear. "They squeezed their way through the fence somehow," said Sergeant Brad Cummings, a spokesman for the Hopkins County Sheriff's office in Sulphur Springs, Texas, about 80 miles (130 km) northeast of Dallas.

Error led to early release for suspected killer of Colorado prison chief

DENVER (Reuters) - A white supremacist parolee suspected of killing Colorado's prisons chief and a pizza delivery man last month had been mistakenly released from prison in January - four years early - due to a clerical error, court officials said on Monday. Evan Spencer Ebel, 28, was killed in a roadside gun battle with police following a high-speed chase in Texas, two days after the March 19 killing of Tom Clements, executive director of the Colorado Department of Corrections.

Source: http://news.yahoo.com/uk-odd-summary-111345568.html

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Microsoft agrees to sell Mediaroom to Ericsson, goes all-in on Xbox

A fortnight after rumors surfaced hinting that Ericsson was lobbying to buy Microsoft's Mediaroom IPTV unit, both companies have announced that a deal has been signed. Microsoft VP Yusuf Medhi blogged that as the Xbox has become the heart of Redmond's home entertainment strategy, Mediaroom has become a resource-hogging distraction. The Mountain View-based IPTV outfit powers AT&T's U-Verse as well as similar VOD services from companies like Deutsche Telekom and Telefonica, and will be folded into Ericsson's Business Support Solutions outfit. The deal's expected to close in the second half of the year, with neither company talking about how much the sale cost.

Filed under: Home Entertainment, Internet, HD, Microsoft

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Iowa Republicans Struggle Against Disarray In Battle For Open Senate Seat

DES MOINES, Iowa ? It was a day Iowa Republicans had long dreamed of when their Democratic nemesis, Tom Harkin, announced he was retiring from the Senate. But that day was in January, and as the Midwest winter now gives way to spring, Republicans here find themselves in a surprising predicament - still trying to come up with someone to run for the job, and struggling to avoid becoming another example of the party's disarray after its presidential defeat.

Ever since Harkin, who had held the office since Ronald Reagan was president, provided an opening for the GOP, the party has bounced between two options for the Senate seat:candidates who could win but won't run, and candidates who could run but, party officials fear, couldn't win.

Meanwhile, the state party apparatus has become a reflection of the GOP's bitterly divided factions. Now led by followers of libertarian Ron Paul, the organization has quarreled with Iowa's senior Republican eminence, Gov. Terry Branstad, and disputed his strategy for state government and party affairs.

"The Republican Party in Iowa is in turmoil, with no clear leader for the future and no consistent governing philosophy," said Doug Gross, a Republican fundraiser and Branstad confidant.

As Democrats line up behind their already-declared candidate for the Senate, Bruce Braley, Republican leaders are hoping they can sort things out before the 2014 campaign heats up and before the 2016 presidential race puts Iowa and its first-in-the-nation caucuses back in the political spotlight. The state party is still trying to get over its experience last year, in which balloting problems at the presidential caucuses left GOP officials unable to declare a winner. National GOP officials plan to discuss the 2016 nominating process, and Iowa's place in it, at a meeting in California this week.

Overall, the Republican Party needs to pick up six seats to win control of the Senate in 2014, and Harkin's would seem to be one of its better chances. A Republican, Charles Grassley, holds the other Senate seat and the party controls the governorship and one house of the Legislature.

But any campaign plan quickly went awry when Branstad's first choice for the race, Rep. Tom Latham, a respected 10-term House member, declined to run.

Meanwhile, Branstad was trying to hold off another Iowa congressman, Steve King, a conservative firebrand who had long eyed the Senate but whom some considered too divisive for a party trying to broaden its appeal. Branstad's delicate diplomacy was upended when a national conservative group publicly called out King as just the kind of lightning rod the GOP should avoid.

But while the barb put King on the defensive, he does not give the impression of a candidate hot to run.

"There can be no scores to settle," King told The Associated Press, saying he was studying poll research. "Of all the opinions out there, I want to make sure there's empirical data."

The search may now turn to Lt. Gov. Kim Reynolds, a working mother and energetic former county officeholder who is popular with social and pro-business conservatives. She has the public blessing of Branstad, but remains untested outside his shadow. Secretary of Agriculture Bill Northey, a well-liked but lower-profile potential fourth option, is waiting to see what Reynolds decides.

"I am surprised we don't have a stronger candidate that's stepped out yet," said Gwen Ecklund, a GOP county chairwoman from western Iowa.

By contrast, the declared Democrat in the race, Braley, a congressman from Waterloo, has been able head off potential Democratic primary challengers and raised $1 million in less than two months.

Adding to the GOP tumult has been the growing power of Ron Paul supporters, who were a nonfactor in the state before Paul placed third in the 2012 Iowa caucuses, higher than many thought possible. Paul's 2012 Iowa caucus campaign chairman A.J. Spiker won election as party chairman last year, and Paul supporters now occupy senior offices on the state GOP committee.

Spiker has attacked a gasoline tax proposal that Branstad was considering supporting and has been crosswise with Branstad's efforts to put the volatile gay marriage issue on the backburner.

Some Republican officials are concerned about attracting any more negative attention to Iowa or prompting any more suggestions that another state should start the presidential nominating calendar ? after the Republican National Committee made an issue of Iowa's botched caucus balloting last year. State GOP officials first declared Mitt Romney had narrowly won, then announced 16 days later that former Sen. Rick Santorum had received more votes ? long after the news could have helped boost his campaign for subsequent early primaries.

An RNC report expressed a strong preference for states using regular elections, rather than caucuses or conventions, for picking nominees.

"I'm concerned because the report calls for doing away with caucuses," said Steve Scheffler, a Republican National Committee member from Iowa.

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Source: http://www.huffingtonpost.com/2013/04/08/iowa-republicans-senate_n_3039221.html

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