“What would happen if we could arrange the atoms one by one the way we want them?” Richard Feynman Fabrication of matter atom by atom remains a long-standing dream and ultimate goal of nanotechnology, following the famous challenge by Feynman 58 years ago. For 30 years, the atom-by-atom fabrication remained the province of visionary thinking […]
Condensed matter • Materials • Physics • Quantum physics • Theoretical physics
The revolutionary theory of topological quantum chemistry , a description of the universal global properties of all possible band structures and materials, diagnoses topological phases based on elementary band representations. A set of bands is topological if it lacks an “atomic limit” that obeys the crystal symmetry (and time reversal, if desired): formally, an atomic […]
Condensed matter • Materials • Nanotechnology • Physics • Quantum physics • Theoretical physics
Chemists have a range of different spectroscopic techniques to study organic molecules. All of these techniques are based on spectra generated by a range of electronic transitions and vibrations, key excitations in matter, the study of which provides information about characteristics of materials and, therefore, allow their identification. In this context, one of those spectroscopic […]
Condensed matter • Materials • Nanotechnology • Physics • Quantum physics • Theoretical physics
The properties of bismuth have long defied classification, placing it in a category of its own. Now, as if it was not enough, it turns out its electronic structure has higher-order topology. This has been shown by an international team with the participation of Maia G. Vergniory (DIPC, Ikerbasque, UPV/EHU) and coordinated by Titus Neupert […]
Condensed matter • Materials • Nanotechnology • Physics • Theoretical physics
Most of the theories describing dynamical processes at surfaces rely on the validity of the adiabatic Born-Oppenheimer approximation. What does this mean? We have already seen that adsorption commonly is understood as the reversible binding of molecules and atoms from the gaseous or liquid phase on surfaces, mostly of highly porous adsorbent media. In chemisorption […]
Metallic glasses are a unique class of materials whose properties combine some of the irreconcilable properties of both metals and polymers. They consist of a combination of metals which, in the solid state, present an amorphous atomic structure, in contrast to common metal alloys, which present a highly ordered microscopic pattern. This lack of crystalline […]
Author: Roberto D’Agosta is an Ikerbasque Research Professor at ETSF and the Department of Materials Physics in the Faculty of Chemistry at the UPV/EHU in San Sebastian. Francesca Baletto, senior lecturer at King’s College London, read and commented the manuscript. Every single moment, nature exploits catalysis to make or improve specific chemical reactions. Catalysts facilitate […]
Atom scattering at low energies has a long history as a useful probe of surface properties. The most common atomic projectiles are helium atoms formed into a monoenergetic beam directed toward the surface with energies in the thermal range, meaning kinetic energies less than 100 meV. From ordered surfaces the scattered spectra consist of sharp […]
Many methods can be used to synthesise non-molecular inorganic solids. Some solids can be prepared by a variety of routes but others, especially those that are not thermodynamically stable, may be much more difficult to prepare and may require special methods. Non-molecular inorganic solids can also be prepared in various forms, as fibres, films, foams […]
Condensed matter • Materials • Quantum physics • Theoretical physics
The wave nature of light expresses itself in the propagation all over space, showing an intrinsic limitation to be localized beyond the so-called diffraction limit which is of the order of half the wavelength of the photons propagating. However when interacting with matter, light often gets reflected, diffracted, scattered or absorbed depending on the interactions […]