The energy landscape of magnetic materials.

Magnetic materials can display many solutions to the electronic-structure problem, corresponding to different local or global minima of the energy functional. In Hartree-Fock or density-functional theory different single-determinant solutions lead to different magnetizations, ionic oxidation states, hybridizations, and inter-site magnetic couplings. The vast majority of these states can be fingerprinted through their projection on the atomic orbitals of the magnetic ions.

[A practitioner's perspective of the latest lipid guidelines].

The latest ESC recommendations propose several interesting new concepts for the practitioner. The recommendations distinguish between the «apparently healthy» patient and the patient at specific cardiovascular risk (diabetes, renal failure, and familial hypercholesterolemia). New risk calculation tools are proposed (SCORE2 and SCORE2-OP).

Topologically protected magnetoelectric switching in a multiferroic.

Electric control of magnetism and magnetic control of ferroelectricity can improve the energy efficiency of magnetic memory and data-processing devices. However, the necessary magnetoelectric switching is hard to achieve, and requires more than just a coupling between the spin and the charge degrees of freedom. Here we show that an application and subsequent removal of a magnetic field reverses the electric polarization of the multiferroic GdMnO, thus requiring two cycles to bring the system back to the original configuration.

Femtosecond control of phonon dynamics near a magnetic order critical point.

The spin-phonon interaction in spin density wave (SDW) systems often determines the free energy landscape that drives the evolution of the system. When a passing energy flux, such as photoexcitation, drives a crystalline system far from equilibrium, the resulting lattice displacement generates transient vibrational states. Manipulating intermediate vibrational states in the vicinity of the critical point, where the SDW order parameter changes dramatically, would then allow dynamical control over functional properties.

Engineering the Optical Emission and Robustness of Metal-Halide Layered Perovskites through Ligand Accommodation.

The unique combination of organic and inorganic layers in 2D layered perovskites offers promise for the design of a variety of materials for mechatronics, flexoelectrics, energy conversion, and lighting. However, the potential tailoring of their properties through the organic building blocks is not yet well understood. Here, different classes of organoammonium molecules are exploited to engineer the optical emission and robustness of a new set of Ruddlesden-Popper metal-halide layered perovskites.