Two-dimensional (2D) materials are an ideal platform to artificially engineer heterostructures with new functionalities due to the weak van der Waals bonding between layers. Monolayers hosting symmetry-broken phases, such as superconductivity, magnetism, ferroelectricity, charge density waves (CDWs), or multiferroicity, represent the most interesting building blocks to design novel phases of matter. One of the main […]
Mermin–Wagner The demand for computational power is increasing exponentially, following the amount of data generated across different devices, applications and cloud platforms. To keep up with this trend, smaller and increasingly energy-efficient devices must be developed, which require the study of compounds not yet explored in data-storage technologies. The discovery of magnetically stable 2D van […]
Yttrium barium copper oxide (YBCO) is a family of crystalline chemical compounds that display high-temperature superconductivity; it includes the first material ever discovered to become superconducting above the boiling point of liquid nitrogen (77 K) at about 93 K. This family is known as cuprates as it can be viewed as containing anionic copper complexes […]
Graphene is a key two-dimensional material that continues to reveal intriguing properties when stacked into just a few layers. But the interesting point is that it is not just a question of a layer sitting on another layer randomly, but how exactly their atoms are positioned in relation to each other. In this vein, for […]
Usually, optical activity is understood as the ability some substances have to change the handedness of polarized light when it goes through them. Molecules that show optical activity have no plane of symmetry. So-called chiral matter broadly describes structures for which left- or right-handed mirror images are non-superimposable, or, equivalently, that lack improper rotation axes […]
Spintronic devices are based on the inherent spin magnetic moment of the electron, the same way electronic ones are on just its charge, to store and process information. These devices should, in theory, operate faster and at lower temperatures than their current electronic-only counterparts because an electron’s spin can be flipped much quicker than its […]
The band theory of metals has been experimentally tested many times and is now the accepted model of the behaviour of conductors and insulators. Electrical resistance is due to collisions of the electrons (whether treated as particles or waves) with impurities, imperfections, and especially the lattice vibrations of the metal crystal. The lattice vibrations of […]
Some materials have special universal properties protected against perturbations. Such properties are theoretically described by topology, a branch of mathematics concerned with the properties of geometrical objects that are unchanged by continuous deformations. So-called topological insulators are electronic materials that have a bulk band gap like an ordinary insulator but have conducting states on their […]
Electron correlations and topology are well established as engines for surprising and potentially functional properties. Strong correlations promote quantum fluctuations, which engender abundant phases of matter and various quantum phase transitions. Meanwhile, extensive developments have taken place in noninteracting electron systems, especially those with sizable spin-orbit couplings. It can reasonably be expected that the intersection […]
Several classes of correlated electron systems such as cuprates, iron-pnictides, iron-chalcogenides, and several heavy-fermion compounds, have been identified as unconventional superconductors. More recently, superconductivity with unconventional features has also been identified in twisted bilayer graphene. In this vein, the electronic correlations intrinsically present in transition metal dichalcogenides (TMDs), a family of layered materials, are promising […]