The device has three electrodes: a niobium injector electrode; a common electrode that consists of a layer of niobium and a layer of aluminium; and a niobium detector electrode. The electrodes are separated by insulating barriers, or junctions, through which current can pass by quantum tunnelling. At the operating temperature of 4.2 Kelvin, all the […]
Helium-6 is a typical neutron-skin nucleus, with two of the neutrons forming a “skin” around the alpha-particle core. Different types of dynamics are possible in such nuclei. In the soft dipole resonance observed by the Japanese group, the alpha particle and neutrons oscillate in opposite directions. In a so-called giant dipole resonance, on the other […]
In harmonic generation a short pulse of intense radiation is focussed into a gas of atoms. The laser-atom interactions are highly nonlinear, and a number of the input photons effectively combine to generate a single output photon with a correspondingly higher energy and shorter wavelength. In most experiments a range of so-called harmonics is produced. […]
Thomas Kuhn is famous for writing the surprise best-seller The Structure of Scientific Revolutions. Who would have thought that a book published in 1962 on the history of science would turn out to be what Steve Fuller claims is the best-known academic book of the second half of the 20th century? So well known is […]
Having just scooped this year’s Aventis Prize for Science Books, Brian Greene’s The Elegant Universe shot back to the top of the best-seller list of physics books for the month of May at Amazon.co.uk, the on-line bookstore. First published over a year ago, Greene’s masterful introduction to string theory was praised by the chairman of […]
In his original thought experiment, Schrodinger imagined that a cat is locked in a box, along with a radioactive atom that is connected to a vial containing a deadly poison. If the atom decays, it causes the vial to smash and the cat to be killed. When the box is closed we do not know […]
Philippe Busquin, the European Union’s commissioner for research, has moved with remarkable speed since he was appointed last September. By January he had published a consultation paper on his big idea, the “European research area” – an initiative that was welcomed by science organizations across Europe – and by last month his plans had received […]
Read article: A new framework for Europe
Optics is widely seen as a key technology for the 21st century
Read article: UK loses ground in optics boom
What is happening to the subject that we have loved and served? More than any other discipline, physics has transformed the face of civilization, particularly during the last century. It has developed techniques and insights that have propelled chemistry, biology and medicine to new heights. It has led to the genesis of modern engineering and […]
Read article: How to survive the 21st century
Spectroscopy – the measurement of the properties of light emitted or absorbed by matter – is one of our most powerful tools to study nature. When a prism is used to separate the light from a flame in which salt has been sprinkled, distinct yellow lines become visible in addition to the usual colours of […]
