In metals like copper and aluminium, conduction electrons move around freely, in the same way as particles in a gas or a liquid.
But when impurities are introduced into the metal's crystal lattice, electrons cluster together in a uniform pattern around the point of interference, resembling the ripples that occur when a stone is thrown into a pool of water. Scientists have now discovered how to strengthen these Friedel oscillations and focus them, almost like using a lens, in different directions.
They've discovered (Nature Communications, DOI: 10.1038/ncomms6558) that at a range of 50 nanometers, these "giant anisotropic charge density oscillations" are many times greater than normal.
A week ago I offered readers of this blog to review a paper I had just written, as its publication process did not include any form of screening (as opposed to what is customary for articles in particle physics, which receive multiple review stages). That's not the first time for me: in the past I did the same with other articles, and usually I received good feedback. So I knew this could work.
I have been given the privilege of publishing during the Beta test period in the Open Access journal The Winnower
for no cost but my time and care. I was also given assistance by the International Journal of Astronomy and Astrophysics
to publish my work on massive star formation there. A work unrelated to the first two, on the LCDM model is in press at ScienceOpen Research
. All of these are Open Access Journals. Two have open peer review and all have post publication commenting.
Bringing the concept of peer review to another dimension, I am offering you to read a review article I just wrote. You are invited to contribute to its review by suggesting improvements, corrections, changes or amendments to the text. I sort of need some scrutiny of this paper since it is not a report of CMS results -and thus I have not been forced by submit it for internal review to my collaboration.
The LHCb experiment collaborators at the Large Hadron Collider have announced discovery of two new particles in the baryon family.
The particles, known as the Xi_b'- and Xi_b*-, were predicted to exist by the quark model but had never been seen before. A related particle, the Xi_b*0, was found by the CMS experiment at CERN in 2012.
A whirlpool of hybrid light-matter particles called polaritons has been created using a spiral laser beam.
Polaritons are hybrid particles that have properties of both matter and light. The ability to control polariton flows in this way could aid the development of completely novel technology to link conventional electronics with new laser and fibre-based technologies.
Polaritons form in semiconductors when laser light interacts with electrons and holes (positively charged vacancies) so strongly that it is no longer possible to distinguish light from matter.
giant LIGO detectors
are switched on in the US next year, they will help scientists pick up the faint ripples of black hole collisions millions of years ago, known as gravitational waves.
Black holes cannot be seen, but scientists hope the revamped detectors, which act like giant microphones, will find remnants of black hole collisions - and theoretical physicists hope experimentalists will give validation for their numerical model.
I am quite happy to report today that the CMS experiment at the CERN Large Hadron Collider has just published a new search which fills a gap in studies of extended Higgs boson sectors. It is a search for the decay of the A boson into Zh pairs, where the Z in turn decays to an electron-positron or a muon-antimuon pair, and the h is assumed to be the 125 GeV Higgs and is sought for in its decay to b-quark pairs.
If you are short of time, this is the bottomline: no A boson is found in Run 1 CMS data, and limits are set in the parameter space of the relevant theories. But if you have a bit more time to spend here, let's start with the beginning - What's the A boson, you might wonder for a start.
If the distribution of dark matter in the region near Earth is lower than it is usually assumed then the interpretation of null results of direct detection efforts must be reconsidered. Astrophysicists have been searching for hard evidence of dark matter for decades. The most favored model has been that dark matter consist weakly interacting massive particles or WIMPS. The basic assumption has been that dark matter is more or less evenly spread through the galaxy with no large scale variations. The work of C. Moni Bidin, R. Smith, G. Carraro, R. A. Méndez, and M.