Quantum Computing? Quantum Bar Magnets in a Transparent Salt

ScienceDaily (June 15, 2012) — Scientists have managed to switch on and off the magnetism of a new material using quantum mechanics, making the material a test bed for future quantum devices.

This image shows the antiferromagnetic arrangement of the spins (colored arrows) in the magnetic salt used by the Swiss-German-US-London team. (Credit: University College London)

The international team of researchers led from the Laboratory for Quantum Magnetism (LQM) in Switzerland and the London Centre for Nanotechnology (LCN), found that the material, a transparent salt, did not suffer from the usual complications of other real magnets, and exploited the fact that its quantum spins -- which are like tiny atomic magnets -- interact according to the rules of large bar magnets. The study is published in Science.

Anybody who has played with toy bar magnets at school will remember that opposite poles attract, lining up parallel to each other when they are placed end to end, and anti-parallel when placed adjacent to each other. As conventional bar magnets are simply too large to reveal any quantum mechanical nature, and most materials are too complex for the spins to interact like true bar magnets, the transparent salt is the perfect material to see what's going on at the quantum level for a dense collection of tiny bar magnets.

The team were able to image all the spins in the special salt, finding that the spins are parallel within pairs of layers, while for adjacent layer pairs, they are antiparallel, as large bar magnets placed adjacent to each other would be. The spin arrangement is called "antiferromagnetic." In contrast, for ferromagnets such as iron, all spins are parallel.

By warming the material to only 0.4 degrees Celsius above the absolute "zero" of temperature where all classical (non-quantum) motion ceases, the team found that the spins lose their order and point in random directions, as iron does when it loses its ferromagnetism when heated to 870 Celsius, much higher than room temperature because of the strong and complex interactions between electron spins in this very common solid.

The team also found that they could achieve the same loss of order by turning on quantum mechanics with an electromagnet containing the salt. Thus, physicists now have a new toy, a collection of tiny bar magnets, which naturally assume an antiferromagnetic configuration and for which they can dial in quantum mechanics at will.

"Understanding and manipulating magnetic properties of more traditional materials such as iron have of course long been key to many familiar technologies, from electric motors to hard drives in digital computers," said Professor Gabriel Aeppli, UCL Director of the LCN.

"While this may seem esoteric, there are deep connections between what has been achieved here and new types of computers, which also rely on the ability to tune quantum mechanics to solve hard problems, like pattern recognition in images."

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China Manned Space Mission successful

The Long March-2F carrier rocket carrying China's manned Shenzhou-9 spacecraft blasts off from the launch pad at the Jiuquan Satellite Launch Center in Jiuquan, northwest China's Gansu Province, June 16, 2012. (Xinhua/Li Gang) JIUQUAN, June 16 (Xinhua) -- Commander-in-chief of China's manned space program Chang Wanquan announced Saturday that Shenzhou-9 spacecraft had accurately entered its orbit, calling the spaceship launch a success. Space.com: You can watch China's Shenzhou 9 launch live online via the state-run CCTV news channel here: http://english.cntv.cn/special/shenzhou9/index.shtml FULL VIDEO: Shenzhou-9 blasts off CCTV News - CNTV English.

We have lift off! China sends woman astronaut into orbit in most ambitious space mission yet

• New hero for a billion people as China's first female astronaut successfully enters space
• The 33-year-old is with two male astronauts on a mission to the 'Heavenly Palace' space station
• The astronauts are now orbiting at 213 miles above Earth and expected to reach the space station on Monday 
• Analysts say China's exclusion from the ISS, largely on objections from the United States, was one of the key spurs for it to pursue an independent program 20 years ago.

By Lawrence Conway

Read more: http://www.dailymail.co.uk/news/article-2160213/We-lift-China-sends-woman-astronaut-orbit-ambitious-space-mission-yet.html#ixzz1y1meGnsk

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Singaporeans living in shoebox, the ‘Mickey Mouse’

Living in a shoebox

Singapore’s ‘Mickey Mouse’ flats are not conducive for raising a family.

A NEW trend has arrived in land-scarce Singapore and it is coined the “shoebox condo” – a tiny apartment just about the size of half a badminton court.

The Singapore government has pledged to put an end to it but private developers have sold nearly 7,000 of these flats that measure less than 500sq ft to young Singaporeans desperate to buy a condo.

They buy them either as a lifestyle choice or but more likely for economic considerations. Property prices have spiralled out of reach for most people.

To developers, this is a potential goldmine if they are allowed to go on, getting a bigger bang for their investments.

But with land growing scarcer, downsizing people’s homes remains a long-term certainty to accommodate the mass influx of foreigners.

The trouble is that these “Mickey Mouse” homes have serious social implication for a nation that desperately needs to get young people to procreate more.

Shoebox condos may be ideal for renting out to foreigners but they are not the best way for the Singapore family and children.

“People have to think hard before buying one,” advises a property agent. “If you decide to settle down and raise a family in future, you’ll find it difficult to do so.”

They also make for a reduced quality of life and the government is trying to discourage the trend through persuasion before taking action. It may, for example, impose a special tax on these units.

So far, these baby apartments have not made an appearance in Singapore’s public Housing Development Board (HDB) estates, which house 80% of the population.

HDB housing, too, has undergone some long-term reduction in size, but is relatively controlled.

According to official statistics quoted by a local newspaper, the average size of a five-room flat in one estate had dropped from 103sq m in 1989 to 91sq m in 2006 – a 12% fall.

In perspective, Singapore’s family size has shrunk even more — from 4.9 to 3.5 persons per family — during the same period, a drop of 28%. As a consequence, officials say, each Singaporean actually has a larger space.

National Development Minister Khaw Boon Wah said he knew of no downsizing of HDB flats during the past 15 years.

The government wants to “maintain a good quality of life” and has no plan to do so.

Home downsizing is a sensitive issue in Singapore, given people’s increasing unhappiness with the government’s immigration open door policy.

The two — housing woes and foreign intake — are related.

Already Singapore, with 7,023 persons living in each sq km of space, has overtaken Hong Kong (6,346 persons) as the third densest-populated city in the world, behind Macau and Monaco.

The former National Development Minister, Mah Bow Tan, had assured Singaporeans that the island was big enough for a 6.5-million population.

There was no need for a massive across-the-board change in development density, he added. The minister was accused of under-building public housing before he was replaced last year.

Shoebox condos are actually not a new invention. Studio apartments had long made the scene in central Singapore.

The smallest recent one measuring only 24sq m (or 258sq ft) is due for completion next year.

A brochure lists this “Mickey Mouse” unit as consisting — believe it or not — of a kitchen, a dining area, bathroom, master bedroom and a living area.

Not only has the average property size in Singapore been reduced to squeeze in more homes, the buildings are being built higher.

In central Singapore, a public residential complex known as The Pinnacle@Duxton has been built consisting of seven 50-storey connected towers.

Singapore is also using more underground space. In more parts of the city, shopping malls, train networks, civil defence shelters and pedestrian links as well as ammunition and oil storage have been built or planned.

Even discounting baby condos, which are a special breed, the average size of a normal private apartment on the island republic has been shrinking over the years.

In the 1970s, a 1,700sq ft flat was considered average; today it is a luxury.

The private property market is fast going the way of Hong Kong and Japan.

Some 30 years ago when I was a working as a journalist in the then British colony, I was living in a 600sq ft two-roomer in the heart of Causeway Bay.

One of my first articles was on housing. It pointed out that the world standard was for a minimum of 55sq ft of space per person.

“Hong Kong provided 24sq ft for each of its residents – slightly bigger than the size of a coffin,” I wrote then.

The official attitude towards baby condos between 2010 (when the government was dealt a strong election rebuff) and this year has changed.

Then Housing Minister Mah seemed happy with its appearance.

He said: “If people want to buy shoebox units and are prepared to pay those prices, why should we stop them?”

His Penang-born successor Khaw, however, wants to discourage the flow.

Singapore’s living density may already be affecting its image abroad. The Ireland-based International Living magazine now ranks Singapore — one of Asia’s wealthiest states — a lowly 70th position among top places to live in.

Is there any sign of change? Unlikely. The former top city planner, Liu Thai Ker, has advised Singaporeans to expect “higher population density”.

“We are near the saturation point of unbearable congestion,” wrote one critic. “Beyond this, Singaporeans may not put up with this kind of stressful living.”

Insight Down South By SEAH CHIANG NEE cnseah05@hotmail.com