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Progress in atomic, optical and quantum science1, 2 has led to rapid improvements in atomic clocks. At the same time, atomic clock research has helped to advance the frontiers of science, affecting both fundamental and applied research. The ability to control quantum states of individual atoms and photons is central to quantum information science and precision measurement, and optical clocks based on single ions have achieved the lowest systematic uncertainty of any frequency standard3, 4, 5. Although many-atom lattice clocks have shown advantages in measurement precision over trapped-ion clocks6, 7, their accuracy has remained 16 times worse8, 9, 10. Here we demonstrate a many-atom system that achieves an accuracy of 6.4 × 10−18, which is not only better than a single-ion-based clock, but also reduces the required measurement time by two orders of magnitude. By systematically evaluating all known sources of uncertainty, including in situ monitoring of the blackbody radiation environment, we improve the accuracy of optical lattice clocks by a factor of 22. This single clock has simultaneously achieved the best known performance in the key characteristics necessary for consideration as a primary standard-stability and accuracy. More stable and accurate atomic clocks will benefit a wide range of fields, such as the realization and distribution of SI units11, the search for time variation of fundamental constants12, clock-based geodesy13 and other precision tests of the fundamental laws of nature. This work also connects to the development of quantum sensors and many-body quantum state engineering14 (such as spin squeezing) to advance measurement precision beyond the standard quantum limit.

The atom may not be a planetary system, but under specific circumstances it can behave like one. That is the curious finding of physicists in Austria and the US, who have confirmed a 1994 prediction that, in the presence of an applied electromagnetic field, electrons in very highly energized atomic states should behave like the Trojan asteroids of Jupiter.

Bohr's model finally not so wrong?

That's the lab I worked...

just being cinical ... but did not we know that g = 9.809 in Paris? I can also create a complex measurement procedure that will held pi = 3.1415, just as expected!!!

well, sure... the interest of such gravimeter is to be absolute, and for now slightly more accurate than the other type of absolute gravimeter which uses retroreflector and interferometry ( http://en.wikipedia.org/wiki/Gravimeter ). While the latter ones reached their limit in term of sensitivity, the atomic ones can be enhanced in many ways (using cooler atoms, better optics, etc...)

A pioneering team from IBM in Zurich has published single-molecule images so detailed that the type of atomic bonds between their atoms can be discerned.

More than a century after the idea was first floated, physicists have finally figured out how to tie water in knots in the laboratory. The gnarly feat, described today in Nature Physics1, paves the way for scientists to experimentally study twists and turns in a range of phenomena - ionized gases like that of the Sun's outer atmosphere, superconductive materials, liquid crystals and quantum fields that describe elementary particles.

Lord Kelvin proposed that atoms were knotted "vortex rings" - which are essentially like tornado bent into closed loops and knotted around themselves, as Daniel Lathrop and Barbara Brawn-Cinani write in an accompanying commentary. In Kelvin's vision, the fluid was the theoretical 'aether' then thought to pervade all of space. Each type of atom would be represented by a different knot.

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Kelvin's interpretation of the periodic table never went anywhere, but his ideas led to the blossoming of the mathematical theory of knots, part of the field of topology. Meanwhile, scientists also have come to realize that knots have a key role in a host of physical processes.

An atomic physics experiment demonstrates a solution to an eighty-year-old quantum conundrum by mimicking in an atom the astronomical problem of a satellite moving in a sun-earth system. How to stabilize a wave packet?

1mm atomic bundle teleported !!!!

Quite intriguing!

this is fantastic! If built, such systems would behave in strange ways, says Achim Rosch, a theoretical physicist at the University of Cologne in Germany, who proposed the technique used by Schneider and his team3. For instance, Rosch and his colleagues have calculated that whereas clouds of atoms would normally be pulled downwards by gravity, if part of the cloud is at a negative absolute temperature, some atoms will move upwards, apparently defying gravity4. Another peculiarity of the sub-absolute-zero gas is that it mimics 'dark energy', the mysterious force that pushes the Universe to expand at an ever-faster rate against the inward pull of gravity. Schneider notes that the attractive atoms in the gas produced by the team also want to collapse inwards, but do not because the negative absolute temperature stabilises them. "It's interesting that this weird feature pops up in the Universe and also in the lab," he says. "This may be something that cosmologists should look at more closely."

cool! i will be working on the link and the data!

Here is a probably definite answer to the strong polemics around the test of gravitational redshift with atom interferometers, which would be far better than the one done by ACES/PHARAO. Read the abstract it's very ACT like, Luzi should like it :) The original Nature paper is the one of Muller, Peters and Chu (the nobel and secretary of energy in the US): http://www.nature.com/nature/journal/v463/n7283/full/nature08776.html

Not really the first time, but they seem to be much closer to be being able to study them. Apparently, they had 38 atoms trapped for miliseconds. Now it's time to prove it behaves just like matter.

A team led by Robert Wolkow at Canada's National Institute for Nanotechnology in Edmonton, Alberta, has discovered that single silicon atoms, sitting in an electron-doped silicon lattice that is blanketed with hydrogen, provide electronic structures with

Positioning via accumulated accelerometer data used to stabilize cold trapped atoms. Current systems are not very reliable for submarines, which cannot use GPS underwater. To create the supersensitive quantum accelerometers, Stansfield's team was inspired by the Nobel-prizewinning discovery that lasers can trap and cool a cloud of atoms placed in a vacuum to a fraction of a degree above absolute zero. Once chilled, the atoms achieve a quantum state that is easily perturbed by an outside force - and another laser beam can then be used to track them. This looks out for any changes caused by a perturbation, which are then used to calculate the size of the outside force.

Amazing! :-D Makes you forget how hard it is to detect individual atoms at all.

While amazing indeed, it makes me wonder how much longer we will still have to wait until all this nanotechnology stuff will deliver something actually useful (say super-efficient/super-small transistors in my cell phone, camera, computer, etc.)? So far it seems to excel mostly in marketing...

A new more efficient type of single photon light source consisting of a quantum dot reproduces 1954 Robert Dicke theoretical proposal. Applications in quantum communications directly on the target. "All light sources work by absorbing energy - for example, from an electric current - and emit energy as light. But the energy can also be lost as heat and it is therefore important that the light sources emit the light as quickly as possible, before the energy is lost as heat."

Researchers in the US and UK say they have invented a new microscopy technique for imaging live tissue with unprecedented speed and resolution. The technique involves using the tiny tip of an atomic force microscope to tap on a living cell and analysing the resulting vibrations to reveal the mechanical properties of cell tissue. The team says that the technique could have widespread applications in medicine. However, another expert in the field suggests that the group has not demonstrated the superiority of the technique to those already available.