Archive for November, 2009

Crystal Quantum Computing?

Monday, November 23rd, 2009

Photo via flickr by colbalt123

Physicists at UC Santa Barbara have made an important advance in electrically controlling quantum states of electrons, a step that could help in the development of quantum computing.

The researchers have demonstrated the ability to electrically manipulate, at gigahertz rates, the quantum states of electrons trapped on individual defects in diamond crystals. This could aid in the development of quantum computers that could use electron spins to perform computations at unprecedented speed.

Using electromagnetic waveguides on diamond-based chips, the researchers were able to generate magnetic fields large enough to change the quantum state of an atomic-scale defect in less than one billionth of a second. The microwave techniques used in the experiment are analogous to those that underlie magnetic resonance imaging (MRI) technology.

The key achievement in the current work is that it gives a new perspective on how such resonant manipulation can be performed. “We set out to see if there is a practical limit to how fast we can manipulate these quantum states in diamond,” said lead author Greg Fuchs, a postdoctoral researcher at UCSB. “Eventually, we reached the point where the standard assumptions of magnetic resonance no longer hold, but to our surprise we found that we actually gained an increase in operation speed by breaking the conventional assumptions.”

While these results are unlikely to change MRI technology, they do offer hope for the nascent field of quantum computing. In this field, individual quantum states take on the role that transistors perform in classical computing.

“From an information technology standpoint, there is still a lot to learn about controlling quantum systems,” said David Awschalom, principal investigator and professor of physics, electrical and computer engineering at UCSB. “Still, it’s exciting to stand back and realize that we can already electrically control the quantum state of just a few atoms at gigahertz rates — speeds comparable to what you might find in your computer at home.”

The work was performed at UCSB’s Center for Spintronics and Quantum Computation, directed by Awschalom.

Via ScienceDaily and University of California – Santa Barbara

In a conversation with Sputnik Observatory, Bernard Haisch, astrophysicist, chronicles the quest to crack the laws of the quantum world; to reveal its mysteries and energies at the microscopic level.

Now what road would we have gone down, if in 1913 Niels Bohr had not just formulated the first of his quantum laws, or what I suppose you would call a quantum fiat, a dictum, a rule that he pulled out of the air, very successfully pulled entirely out of the air. And the question is, what would have happened to physics had he not done that? Would we have developed the idea of a sea of energy, zero point energy filling the universe, and investigating the consequences of that, and perhaps discovering that some of the quantum mysteries of the time could have been resolved using that approach, rather than the development of a whole new physics? That, of course, is a question no one can answer because that’s the road we didn’t go down. And who knows what kind of discoveries we would have made on a road we didn’t go down 75 years ago? But within the last thirty years that road has been taken up again by a few explorers. And one of the earliest explorers was a physicist, a British physicist named Trevor Marshall, who in 1963, I would say perhaps did not single-handedly resurrect, but certainly was one of the key figures in resurrecting this old way of thinking of space as being filled with a sea of zero point energy, and applying the ordinary laws of classical Newtonian physics to whatever circumstances we want it to represent to model, but adding to classical physics the idea of an underlying sea of zero point energy. He developed this approach and it was taken up a few years later by a very clever scientist, at the City University of New York, named Timothy Boyer, who took it much further. And together, over the next ten years, I don’t think they worked together, but together in public, publication of papers side by side, this approach was taken. This was, to some extent, the road that had been abandoned fifty years ago. And their objective was to try to develop the understanding of quantum laws using this semi-classical representation. And so you ask yourself, we have all sorts of quantum mysteries that have been explored and discovered since the 1920s, that presumably required the existence of a set of laws that are purely quantum, they’re not intuitive. It’s been said that if you think you understand quantum mechanics, that’s proof by definition that you don’t, because the laws are not intuitive, they don’t seem to make sense, they seem to contradict our everyday experience, and yet it’s been a highly successful way to develop our understanding of the microscopic world.

The WISE Mission

Tuesday, November 17th, 2009

Photo of WISE arriving at Vandenberg Air Force Base. Credit: NASA.

WISE, or the Wide-field Infrared Survey Explorer, is scheduled to blast into space in December aboard a United Launch Alliance Delta II rocket from NASA”s Space Launch Complex 2. Orbiting the Earth, WISE will scan the entire sky at infrared wavelengths to unveil all sorts of unseen cosmic treasures.

This infrared surveyor will pick up not only hundreds of thousands of new asteroids in our main asteroid belt, and hundreds of near-Earth objects, but will uncover the coldest stars, called brown dwarfs, perhaps even one closer to us than our closest known neighbor, Proxima Centauri, which is 4 light-years away. More distant finds will include nurseries of stars, swirling planet-building disks and the universe’s most luminous galaxies billions of light-years away.

The data will help answer fundamental questions about how solar systems and galaxies form, and will provide the astronomical community with mountains of data to mine.

The mission will scan the sky from a sun-synchronous orbit, 500 kilometers (about 311 miles) above Earth. After a one-month checkout period, it will map the whole sky over a period of six months.

NASA’s Jet Propulsion Laboratory (JPL) manages the Wide-field Infrared Survey Explorer for NASA’s Science Mission Directorate. The science instrument was built by the Space Dynamics Laboratory, Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Science operations and data processing will take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.

Via NASA

Magnetic Fields in Motion

Wednesday, November 11th, 2009

Photo via Magnetic Movie by Ruth Jarman and Joe Gerhardt

In Magnetic Movie, the secret lives of invisible magnetic fields are revealed as chaotic ever-changing geometries. All action takes place around NASA’s Space Sciences Laboratories, UC Berkeley, to recordings of space scientists describing their discoveries. Actual VLF audio recordings control the evolution of the fields as they delve into our inaudible surroundings, revealing recurrent ‘whistlers’ produced by fleeting electrons.

Ruth Jarman and Joe Gerhardt of Semiconductor, artists-in-residence at the Space Sciences Laboratory, have taken the magnificent scientific visualizations of the sun and solar winds conducted at the Space Sciences Laboratory and “semiconducted” them.

With Magnetic Movie, the artists have tapped into a new and ancient aesthetic of turbulence. We can hear it in the sounds of natural radio— naturally-occurring electromagnetic signals from the earth’s ionosphere and magnetosphere— that course through Magnetic Movie.

Are we observing a series of scientific experiments, the universe in flux, or a documentary of a fictional world?

Magnetic Movie from Semiconductor on Vimeo.

Switching on the Smart Gene

Monday, November 9th, 2009

Photo via flickr by mandykoh

Over-expressing a gene that lets brain cells communicate just a fraction of a second longer makes a smarter rat, report researchers from the Medical College of Georgia and East China Normal University.

Dubbed Hobbie-J after a smart rat that stars in a Chinese cartoon book, the transgenic rat was able to remember novel objects, such as a toy she played with, three times longer than the average Long Evans female rat, which is considered the smartest rat strain. Hobbie-J was much better at more complex tasks as well, such as remembering which path she last traveled to find a chocolate treat.

The report comes about a decade after the scientists first reported in the journal Nature that they had developed “Doogie,” a smart mouse that over-expresses the NR2B gene in the hippocampus, a learning and memory center affected in diseases such as Alzheimer’s. Memory improvements they found in the new genetically modified Long Evans rat were very similar to Doogie’s. Subsequent testing has shown that Doogie maintained superior memory as he aged.

“This adds to the notion that NR2B is a universal switch for memory formation,” says Dr. Joe Z. Tsien, co-director of the MCG Brain & Behavior Discovery Institute and co-corresponding author on the paper published in PLoS ONE. Dr. Xiaohua Cao at East China Normal University also is a co-corresponding author.

The finding also further validates NR2B as a drug target for improving memory in healthy individuals as well as those struggling with Alzheimer’s or mild dementia, the scientists says.

Scientists found that Hobbie-J consistently outperformed the normal Long Evans rat even in more complex situations that require association, such as working their way through a water maze after most of the designated directional cues and the landing point were removed. “It’s like taking Michael Jordan and making him a super Michael Jordan,” Deheng Wang, MCG graduate student and the paper’s first author, says of the large black and white rats already recognized for their superior intellect.

via PhysOrg.com and PLoSone.org

Can Light Run Our Electronics?

Thursday, November 5th, 2009

Photo via flickr by Dead Air

“If you open up almost any electronic gadget, you will see various elements that are operating using electric circuitries,” explains scientist Nader Engheta.  “Many of them have different functionalities, such as inductors, capacitors, resistors, transistors, and so forth. These well-known elements have been around for decades. But what if you could bring these concepts to the nanoscale, and what if they could operate with light instead of electricity?”

Engheta, a scientist at the University of Pennsylvania, along with Andrea Alů, believes that it is possible to create a nanoscale circuit board that has the potential to be useful in communications.

There are three main advantages of using optical nanoparticle circuit boards, Engheta says. First of all, being able to further miniaturize various communications devices would ensure that technology continues to evolve. “We are moving toward having more and more information compacted into a smaller volume.” The second advantage is that using optical frequencies would provide more bandwidth. Finally, there is a very real possibility that nanoscale circuit boards, properly constructed, would use less energy. “We have to look more into this possibility, but it is quite likely that optical nanoparticle circuit boards would be low energy in nature,” Engheta insists.

One of the biggest challenges to realizing this type of nanoscale circuitry is that it is difficult to form the structures needed at such a small size. So far, Engheta and Alů have only used computer simulations to test their ideas related to nanoscale circuit boards.

via PhysOrg.com

Exhaust Makes Electricity

Monday, November 2nd, 2009

Photo via flickr by AlbinoFlea

The Air Force Office of Scientific Research and the National Science Foundation are funding research that may result in a military turbine aircraft that for the first time ever will produce its own electricity from exhaust heat generated from thermo electricity.

Dr. Daryoosh Vashaee and a team of co-researchers at Oklahoma State University’s Helmerich Advanced Technology Research Center in Tulsa are using thermo electric nanotechnology to investigate the conversion of waste heat into electricity.

Up to this point, thermo electricity has not been used extensively beyond space and cooling applications because it could not be produced efficiently. However, the scientists’ efforts in Oklahoma may soon change that and thermo electric technology may be heralded by the Air Force in a way that no other eco-friendly energy source has, because it has non-toxic emissions.

Vashaee and his co-researchers are examining thermo electric versus infrared technology, which is what the Air Force is currently using. The latter requires liquid nitrogen to cool down the infrared cells. Thermo electricity,  on the other hand, would not make that necessary and it would also be inexpensive.

“The new thermo electric sensors also provide a means to make high performance infrared detectors that are structurally simple and small, suitable for being used in military missions,” said Vashaee.

Vashaee noted that the next step is to develop thermo electric modules that can be used for power generation for Air Force aircraft, solar, thermal cells and waste heat recovery systems used in industry.

via PhysOrg.com