Related papers: Canonical magnetic insulators with isotropic magne…
Topological insulators are characterized by the presence of gapless surface modes protected by time-reversal symmetry. In three space dimensions the magnetoelectric response is described in terms of a bulk theta term for the electromagnetic…
We derive the effective charge- and current-density operators for the strong-coupling limit of a single-band Mott insulator in the presence of spin-orbit coupling and show that the spin-orbit contribution to the effective charge density…
We consider dilute magnetic doping in the surface of a three dimensional topological insulator where a two dimensional Dirac electron gas resides. We find that exchange coupling between magnetic atoms and the Dirac electrons has a strong…
Metal-insulator transitions in pyrochlore iridates (A2Ir2O7) are believed to occur due to subtle interplay of spin-orbit coupling, geometric frustration, and electron interactions. In particular, the nature of magnetic ordering of iridium…
Recent theories and experiments have suggested that strong spin-orbit coupling effects in certain band insulators can give rise to a new phase of quantum matter, the so-called topological insulator, which can show macroscopic entanglement…
We observe a bilinear magnetic field-induced electric polarization of 50 $\mu C/m^2$ in single crystals of NiCl$_2$-4SC(NH$_2$)$_2$ (DTN). DTN forms a tetragonal structure that breaks inversion symmetry, with the highly polar thiourea…
For many spin systems with constant isotropic antiferromagnetic next-neighbour Heisenberg coupling the minimal energies E_{min}(S) form a rotational band, i.e. depend approximately quadratically on the total spin quantum number S, a…
Topological quantum chemistry (TQC) classifies the topological phases by real-space invariants in which obstructed atomic insulators belong to the trivial case but sometimes show the feature of higher-order topological insulator. Here, for…
A key feature of topological insulators is the robustness of the electron energy spectrum. At a surface of a topological insulator, Dirac point is protected by the characteristic symmetry of the system. The breaking of the symmetry opens a…
Spin correlations in metallic and insulating phases of $V_2O_3$ and its derivatives are investigated using magnetic neutron scattering. Metallic samples have incommensurate spin correlations varying little with hole doping. Paramagnetic…
We report low-temperature powder X-ray and neutron diffraction studies on breathing pyrochlore magnets Cu$M$Cr$_{4}$S$_{8}$ ($M$ = Al, Ga), which undergo a magnetic transition at $T_{\rm N} \approx$ 21 and 31 K for {$M$ = Al and Ga,…
Magnetoelectric crystals have the interesting property that they allow electric fields to induce magnetic polarizations, and vice versa, magnetic fields to generate ferroelectric polarizations. Having such a magnetoelectric coupling usually…
In this work we study the possible occurrence of topological insulators for 2D fermions of high spin. They can be realized in cold fermion systems with ground-state atomic spin $F>\tfrac{1}{2}$, if the optical potential is properly…
We propose that the topological magneto-electric (ME) effect, a hallmark of topological insulators (TIs), can be realized in thin films of TIs in the $\nu=0$ quantum Hall state under magnetic field or by doping two magnetic ions with…
The influence of the spin-orbit coupling on the magnetic structure of deposited transition metal nanostructure systems has been studied by fully relativistic electronic structure calculations. The interplay of exchange coupling and magnetic…
We investigate a single magnetic impurity in the presence of strong spin-orbit coupling and single-ion anisotropy. We show that at sufficiently strong coupling there exists a finite temperature window, before the moment is completely…
Couplings between ferroelectric and magnetic orders offer promising routes toward low-dissipation electronics. However, such couplings are notably rare, largely due to the poor compatibility between insulating band structures and…
Chiral magnets are an emerging class of topological matter harbouring localized and topologically protected vortex-like magnetic textures called skyrmions, which are currently under intense scrutiny as a new entity for information storage…
Magnetic topological materials are a class of compounds which can host massless electrons controlled by the magnetic order. One such compound is EuZn$_2$Sb$_2$, which has recently garnered interest due to its strong interplay between the Eu…
The discovery that the band structure of electronic insulators may be topologically non-trivial has unveiled distinct phases of electronic matter with novel properties. Recently, mechanical lattices have been found to have similarly rich…