Beginning in 1928, Felix Bloch, an assistant to Werner Heisenberg in Leipzig, began to make some realistic assumptions in an attempt to formulate a more complete quantum mechanics of electrical conductivity. First, because he wanted to assign a definite momentum and energy to each of the electrons, but not a definite position or a time […]
Common glass, used in windows or bottles, for example, is made by heating a mixture of calcium oxide (lime), sodium carbonate (soda), and silicon (IV) oxide (sand), resulting in a calcium silicate. This silicate is not a crystal but a solid in which atoms are random and have no long-range orderd pattern. These kind of […]
When we approximate two superconducting materials at low temperature, so that they are only separated by a very thin layer (less than 10 nanometres thick) of an insulating material, some new and very interesting electrical effects can be observed. If normal conducting metals are separated by such a barrier in that conditions it is possible […]
Amputees are people that have had a limb removed by trauma, medical illness, or surgery. In this latter case, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. Nevertheless, most new amputations occur due to complications of the vascular system, especially from diabetes. It is […]
Imagine a very simple chemical estructure: 4 carbon and 1 nitrogen forming a ring, with no double bonds, just simple bonds between any two of them and with hydrogen. This compound is called pyrrolidine and is the base of very important biological and farmacological products. Pyrrolidine is found naturally in the leaves of tobacco and […]
Chemistry • Condensed matter • Materials • Physics • Quantum physics
Faster. That is the word that describes de evolution of electronics. Any new development has to be faster than anything before, if it is going to cope with the huge amount of information that the device where it may be incorporated will have to process in almost no time. Graphene has just demonstrated once again […]
The other day I came across an article about the revolution of cultured meat at El País Semanal, although that was not the first time I read about this. Still, I have to admit is such a shocking subject that I thought it may deserve a post explaining how advanced this technology is at the […]
A topological insulator is a material in which there is order associated to topology, i.e., the surface can conduct electricity but the bulk of the material is an insulator. In these last years topological insulators have received the attention of a large area of the scientific community thanks to their exotic properties. They are promising […]
Geometrical structure, lattice periodicity and atomic arrangement are subtly intertwined with the electronic properties of materials. Sub-angstrom changes in the atomic distance are sufficient to modify the physical and chemical properties, such as the band-structure, carrier mobility and the chemical reactivity. The deposition of two-dimensional layered crystals on mechanically stretchable or bendable substrates can produce […]
Condensed matter • Materials • Nanotechnology • Quantum physics
When we study for the first time the structure of the atom in high school we encounter for the first time the concept of quantum excitation. We learn that excitation is the process in which a nucleus, electron, atom, ion, or molecule acquires energy that raises it to a quantum state (the excited state) higher […]