Bulk-suppressed and surface-sensitive Raman scattering by transferable plasmonic membranes with irregular slot-shaped nanopores.

Raman spectroscopy enables the non-destructive characterization of chemical composition, crystallinity, defects, or strain in countless materials. However, the Raman response of surfaces or thin films is often weak and obscured by dominant bulk signals. Here we overcome this limitation by placing a transferable porous gold membrane, (PAuM) on the surface of interest.

Temporal and spatial tracking of ultrafast light-induced strain and polarization modulation in a ferroelectric thin film.

Ultrashort light pulses induce rapid deformations of crystalline lattices. In ferroelectrics, lattice deformations couple directly to the polarization, which opens the perspective to modulate the electric polarization on an ultrafast time scale. Here, we report on the temporal and spatial tracking of strain and polar modulation in a single-domain BiFeO thin film by ultrashort light pulses.

Magnetoelectric transfer of a domain pattern.

The utility of ferroic materials is determined by the formation of domains and their poling behavior under externally applied fields. For multiferroics, which exhibit several types of ferroic order at once, it is also relevant how the domains of the coexisting ferroic states couple and what kind of functionality this might involve. In this work, we demonstrate the reversible transfer of a domain pattern between magnetization and electric-polarization space in the multiferroic DyTbFeO.

Metastable disordered phase in flash-frozen Prussian Blue analogues.

A new metastable phase in flash-frozen disordered Prussian blue analogues is reported. The phase is characterised by the appearance of diffuse scattering clouds and the reduction of the local structure symmetry: from cubic to a tetragonal or lower space group. The phase transition is characterised by the translational modulation of the structure and is likely caused by the freezing of the water confined in the pores of the structure.

Emerging spin-phonon coupling through cross-talk of two magnetic sublattices.

Many material properties such as superconductivity, magnetoresistance or magnetoelectricity emerge from the non-linear interactions of spins and lattice/phonons. Hence, an in-depth understanding of spin-phonon coupling is at the heart of these properties. While most examples deal with one magnetic lattice only, the simultaneous presence of multiple magnetic orderings yield potentially unknown properties.

Magnetoelectric coupling of domains, domain walls and vortices in a multiferroic with independent magnetic and electric order.

Magnetically induced ferroelectrics exhibit rigidly coupled magnetic and electric order. The ordering temperatures and spontaneous polarization of these multiferroics are notoriously low, however. Both properties can be much larger if magnetic and ferroelectric order occur independently, but the cost of this independence is that pronounced magnetoelectric interaction is no longer obvious.

Direct observation of polar tweed in LaAlO3.

Polar tweed was discovered in mechanically stressed LaAlO3. Local patches of strained material (diameter ca. 5 μm) form interwoven patterns seen in birefringence images, Piezo-Force Microscopy (PFM) and Resonant Piezoelectric Spectroscopy (RPS).

Interplay of chemical structure and magnetic order coupling at the interface between Cr₂O₃ and Fe₃O₄ in hybrid nanocomposites.

Hybrid nanocomposites based on ferrimagnetic (FiM) Fe3O4 and magnetoelectric antiferromagnetic (AFM) Cr2O3 nanocrystals were synthesized to offer a particular three-dimensional (3D) interface between the two oxides. This interface favours an intermixing process (demonstrated by combining Raman spectroscopy and magnetization measurements) that determines the final magnetic behavior.

Structures and magnetism of the rare-earth orthochromite perovskite solid solution LaxSm1-xCrO3.

A new mixed rare-earth orthochromite series, LaxSm1-xCrO3, prepared through single-step hydrothermal synthesis is reported. Solid solutions (x = 0, 0.25, 0.