Chemistry • Condensed matter • Quantum physics • Theoretical physics
Imagine there exist a material in which an electron could be split into two quasiparticles. These two quasiparticles both would carry electric charge, move in opposite directions but could not move backwards. Furthermore these quasiparticles would be massless. And we can give them a fancy name, Weyl fermions. This seems to be at odds with […]
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 […]
When light encounters molecules, the predominant mode of scattering is elastic scattering (Rayleigh). This scattering is responsible for the blue colour of the sky, for example. It is also possible for the incident photons to interact with the molecules in such a way that energy is either gained or lost so that the scattered photons […]
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 […]
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 […]
Unfortunately, this interesting story is coming to an end. In the previous post we already disscussed the first loophole-free Bell experiment, but if this experiment was conclusive the story is closed. Why are we still discussing it? It happens sometimes in History that people look to solve a problem for decades and suddenly two different […]
In previous posts, we have reviewed the different loopholes of Bell experiments. To make a long story short, entanglement experiments are based on measuring some magnitudes in two quantum systems, calculating a value based on the outcomes of these measurements, and if this value goes beyond a certain threshold we can say that the universe […]
Chemistry • Condensed matter • Materials • Physics • Quantum physics
Graphene is a two-dimensional allotrope of carbon made of hexagons. In February 2015, penta-graphene, only made of pentagons, was theoretically proposed as another two-dimensional allotrope of carbon . Apparently, it is dynamically, thermally, and mechanically stable, exhibiting a large band gap (graphene is gapless). However, an exhaustive experimental search has been inconclusive, resulting in doubts […]
In order to study new solid state magnetic properties appropiate new laboratory models are needed. In particular, there is a necessity for a substrate to investigate new forms of magnetic coupling with nanoscale ferromagnets and the exotic physics at the interface with semiconductor or superconductor materials. Now a team of researchers from DIPC and some […]
An atom in an excited state gives off energy by emitting a photon, a quantum of electromagnetic radiation, according to Bohr’s second postulate. Although Bohr’s specific model of the atom has been vastly extended and incorporated into models based on a different approach , this postulate is still valid. Atoms can acquire internal energy, that […]