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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Malaysian gutter politics: sex video, like a blast from the past to end up as Three Stooges?

It's like a blast from the past
On The Beat By Wong Chun Wai

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There is a sense of déjà vu in the sex video case but this time, public expectations seem to have changed.

IT’S now called a sex video and the footage is probably only contained in a thumb drive. But 22 years ago, during the analogue days, they came in the form of the bulky VHS (video home system) tapes.

The visual on tape was often poor and grainy, especially if taken with a hidden camera and in bad lighting. But if they involved political figures, the intrigue and curiosity created would have been no less strong.

There would be the typical open declaration of disgust and anger over such intrusion of privacy but most would want to know more, especially the identities of the people involved.

The controversy over the sex video involving a man resembling Opposition Leader Datuk Seri Anwar Ibrahim is like a replay of an old video, or “rewind” as it used to be called.


Twenty-two years ago, DAP’s Karpal Singh walked into the Dewan Rakyat with an expose of a sex video implicating then Dewan Rakyat deputy speaker D.P. Vijandran. The press was tipped off earlier about this tape, which purportedly featured the bachelor politician and a woman in a yellow saree.

Karpal told Parliament then that he was exposing the MIC leader in “public interest” while then Prime Minister Dr Mahathir Mohamad expressed regret that the issue had been exploited so much that those allegedly involved were being “persecuted”.

At the height of the issue, this writer received a call from Vijandran who pleaded for the story not to be reported. He also called reporter K.P. Waran at the New Straits Times, hoping for the same thing. But we both told him that it would not be possible.

He then issued a statement criticising the Opposition’s call for the setting up of a Special Tribunal or Royal Commission of Inquiry.

There is certainly a sense of déjà vu among veteran journalists today.

Karpal Singh was regarded as quite a hero for his expose then, and even MIC boss S. Samy Vellu was asked by DAP to resign because of the controversy.

Vijandran, who was then the MIC secretary-general, denied he was the man in the video. In fact, when the issue went to court, he maintained that it was not him.

Political enemies would be blamed but, like most sex videos, they are often the work of people closest to the politician. Blaming the former is often a political reaction.

In Vijandran’s case, he blamed his nephew, S. Ravindran, for using a hidden camera to film him in a compromising situation. In his affidavit, he accused Ravindran of “splicing and superimposing his (Vijandran) image onto the pornographic tape portraying him as an actor”. In short, the tape was doctored. It wasn’t him, he maintained.

Fast forward to the present. No one would claim credit for such gutter politics but the Datuk Trio of Tan Sri Rahim Tamby Chik, Datuk Shazryl Eskay Abdullah and Datuk Shuaib Lazim have unprecedentedly taken responsibility for their action. They are also claiming “public interest” as grounds for doing what they did.

Eskay, a former physiotherapist to Anwar and who is said to be the closest to the Opposition Leader, even signed off a press release as “the insider” and dropped hints that he knew more.

Rahim has rebutted allegations that he had an old political score to settle with Anwar. Not many political analysts, however, are convinced.

Umno leaders have said Rahim has not done the party a favour and they are privately saying he lacks credibility. Many have said they are being blamed for something they had no hand in and that they are nervous over how the drama would end.

In 1998, Umno Youth leader Ruslan Kassim, who was aligned to Anwar, alleged that Rahim was the publisher of the book 50 Reasons Why Anwar Cannot Be PM.

Rahim retaliated by suing him for RM15mil. The case only ended in 2004 with Ruslan, who had by then joined PKR, making an open apology to the former Malacca Chief Minister.

Old soldiers may fade away but in Malaysia it would appear that old political enemies will stay on to renew their fights. Anwar certainly has plenty of old enemies both inside and outside his party.

The trio has called for foreign experts to verify the identity of the man in the video.

Interestingly, during Vijandran’s trial, Dr Alfred David Linney, a University College of London specialist in planning and assessment of facial reconstruction, said the actor in the tape was a different person.

In fact, the defence witness testified that “if both the men were the same person, then their facial angles will not differ very much”.

Another defence witness, Japanese forensic anthropologist Masatsugu Hashimoto, testified: “It is wrong to state that the two earlobes of the man are the same because at least 14 points of similarities should have been found. In this case, not even a single point of similarity was found.”

Another defence witness, a lawyer, said he viewed the tape for 75 minutes and did not recognise the actor. When asked if he was sure, he replied: “I am positively sure it wasn’t Vijandran.”

The point is: in a court case, the prosecution and defence can always get witnesses, even so-called experts, to testify in support of their case.

In that instance, with the tapes freely available, the public had formed their own conclusion. In the People’s Court, Vijandran was the actor. Forget about the foreign experts.

In 1994, the Sessions Court sentenced him to a month’s jail and a fine of RM2,000 for fabricating evidence and making a false declaration. He took his appeals to the various upper courts and finally in 1998, he was acquitted by the Court of Appeal, which also set aside his conviction and sentence. But his political career was dead and public opinion of him and the tape remains unchanged.

This time around, however, public expectations seemed to have changed. Most Malay­sians do not believe Anwar is the man in the video even though they haven’t seen it. And even if they did, the die-hard Anwar supporters would regard the use of the video as gutter politics.

If the Datuk Trio had thought they could play heroes, they have found out that the psychological battle has become more complicated. Un­like Vijandran’s tape, only 10-odd journalists, some policemen and a few local film experts have seen the video, not 20 million people. The police have said the video is genuine, so the three Datuks had better plan their next steps carefully if they do not want to end up as the Three Stooges.