Elements with 4f or 5f electrons in unfilled electron bands and their componuds , which have ions carrying magnetic moments but do not magnetically order, or only do so at very low temperatures, are generally known as heavy-fermion or heavy electron systems because the scattering of the conduction electrons with the magnetic ions results in […]
Condensed matter • Materials • Physics • Quantum physics • Theoretical physics
We all know what an insulator is, don’t we? An insulator is any substance that is a poor conductor of heat and electricity. Both properties ussually occur as a consequence of a lack of mobile electrons.If we want to dive a little deeper into the nature of insulators we make use of energy band theory […]
The scattering of conduction electrons in metals owing to impurities with magnetic moments is known as the Kondo effect, after Jun Kondo, who analysed the phenomenon in 1964. This scattering increases the electrical resistance and has the consequence that, in contrast to ordinary metals, the resistance reaches a minimum as the temperature is lowered and […]
Last February I published my first scientific article as principal author in Physical Review B . This article summarizes a big part of my work as a PhD student, a journey that has not been easy. The first version was sent to the journal a year ago; in between many things happened: new experiments, discussions […]
Since the discovery of graphene, a wide diversity of atomic-layer-thick, two-dimensional (2D) materials with varied properties have emerged. Of particular interest are those that exhibit semiconducting behavior, such as hexagonal boron nitride (hBN). hBN is isoelectronic to graphene and has also a honeycomb lattice formed by alternating nitrogen and boron atoms, but in contrast to […]
So-called “valleytronics” is a new type of electronics that could lead to faster and more efficient computer logic systems and data storage chips in next-generation devices. Valley electrons are so named because they carry a valley degree of freedom, a pseudospin. This is a new way to harness electrons for information processing that’s in addition […]
With the possible exception of Avogadro’s number, which was in reality defined and made popular by Stanislao Cannizzaro, many things in the sciences are usually named after the person who makes them popular. The Seebeck effect is an example. Originally discovered in 1794 by Alessandro Volta, it is named after Thomas Johann Seebeck, who in […]
Biology • Biomedicine • Computer science • Nanotechnology • Neuroscience • Physics
In 1873, the microscopist Ernst Abbe stipulated a physical limit for the maximum resolution of traditional optical microscopy: 0.2 micrometers, or 200 nanometers (the shortest wavelength for visible light, the extreme limit of violet). This meant that scientists could distinguish whole cells, as well as some parts of the cell called organelles. However, they would […]
Wildfires are a major problem with a strong impact on human life, property and the environment, Global warming and a legacy of poor management are the forces behind the increase in their occurrence and in their magnitude measured in extension. In 2017, an unusual number of extensive and severe wildfires occurred in many parts of […]
Experiments performed in 1909 by Geiger and Marsden, also called Rutherford gold foil experiment because Rutherford was their supervisor, led to the discovery of nuclear structure in the atom: the nucleus of the atom is its central core and contains most of its mass and the nucleus is positively charged. Further research during the next […]