Modern technologies in all fields (information, communications, medicine, etc.) are based on the properties of materials on the atomic scale, whether they are metals, semiconductors, magnets or superconductors. These properties go beyond those of the atoms from which these materials are made. Just as the structure of these atoms must be understood using quantum physics, these often unusual properties must be understood using the laws of quantum physics, taking into account the interactions of a large number of atoms. “Quantum materials” are materials whose unusual properties (e. g. superconductivity) cannot be understood by simple models involving only one atom or one electron at a time, but which require consideration of the” collective “effects of a large number of electrons in constant interaction.
Superconductors, which lose all electrical resistance at low temperatures, are the most striking example of a quantum material. Magnets of all kinds (ferromagnets, antiferro-magnets, etc.) are also quantum materials. Some materials are even volume insulating, but conductive on the surface, with robustness of behaviour due to “topological” properties. “Artificial” materials can also be made, atomic layer by atomic layer, whose unusual properties can be configured or used in electronic devices.
The Institut quantique houses internationally recognized laboratories dedicated to the study of quantum materials. Experimental physicists test materials under extreme temperature, magnetic field and pressure conditions to reveal the collective behaviour of electrons that determine their properties and applications. Theoretical physicists use supercomputers to predict or explain these properties from simple models of these materials.