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Ultrathin films of highly monodispersed luminescent Si nanoparticles are directly integrated on polycrystalline Si solar cells. The authors monitor the open-circuit voltage and the short circuit current. The results demonstrate that films of 1 nm blue lu

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.

"Our system of five clocks connects with an unprecedented consistency the optical and the microwave worlds." Interesting?

Be careful, the article is written by the company who did the migration to Ubuntu. Here is a comment by a police guy from IT (in french...). In brief he says that tyhe migration was not a problem for most of the people; exepc for some probleme with access. But it did cost money ! and the saving was not the main argument. "Personnellement concerné par la news qui n'en est pas une, je peux vous assurer que le message de Canonical est surtout commercial... Le choix d'Ubuntu est dû à son hégémonie et le fait que ce soit basé sur du Debian qui est considéré comme très stable. La distrib est d'une maintenance plus aisée que la plupart de celles qui ont été testées. "4500 postes" veut dire "4500 unités de gendarmerie" donc dans les brigades que vous connaissez... Pour ce qui est d'OpenOffice, le passage s'est fait assez tranquillement sauf pour les applis Access qui ont eu un peu de mal à passer sur le module Base...La plupart ont été reprise au sein d'applis php/mysql ou d'applis centralisées... Aujourd'hui, les gendarmes qui je le rappelle ne sont pas informaticiens mais vivent pour vous (au sens le plus strict je vous l'assure) utilisent donc firefox/thunderbird et oppenoffice en clients lourds, le reste étant des applis sur l'intranet ou "invisibles" pour l'utilisateur. Le passage à Ubuntu ne gène en rien dans l'utilisation car le trio précédemment cité est déjà connu et maîtrisé par nombre de mes collègues. Je ne suis pas censé m'exprimer en lieu et place de mes supérieurs mais à titre personnel, le choix d'Ubuntu est un choix intelligent car c'est une distribution avec une prise en main très accessible et avec une maintenance vraiment aisée pour les spécialistes informatiques dont je fais partie...Il ne faut pas oublier qu'une distribution plus élitiste aurait été maîtrisée par moins de monde et donc la maintenance aurait été plus coûteuse... Donc aujourd'hui nous "maîtrisons" cette part de notre infrastructure et la trans

Lotus Notes doesn't run on Linux anyway...

on space turism (italian)

Quoted from one of the authors in a separate interview: "We know that the spin states of atomic nuclei associated with semiconductor defects have excellent quantum properties at room temperature," said Awschalom, Liew Family Professor in Molecular Engineering and a senior scientist at Argonne National Laboratory. "They are coherent, long-lived and controllable with photonics and electronics. Given these quantum 'pieces,' creating entangled quantum states seemed like an attainable goal." Bringing the quantum world to the macroscopic scale could see some interesting applications in sensors, or generally entanglement-enhanced applications.

They were previously working on the same concept in N-V centers in diamond (as a semiconductor). Here the advantage is that SiC could in principle be integrated with Si or Ge. Anyway its all about controlling coherence. In the next 10 years some breakthroughs are expected in the field of semiconductor spintronics, but quantum computing in this way lies still in the horizon