Related papers: Uncompensated Polarization in Incommensurate Modul…
Perovskite solid solutions PbHfO3-PbSnO3 offer valuable opportunities for studying the formation mechsnisms of incommensurate phases, owing to the presence of an intermediate (between cubic and incommensurate) phase, which is stabilized in…
Hybrid Improper Ferroelectricity (HIF) allows the generation of an electrical polarization in the AA'BB'O$_6$ double perovskite materials thanks to the combination of two non-polar octahedral distortions. Nevertheless, for selected…
The incompatibility of partial d occupation on the perovskite B-site with the standard charge transfer mechanism for ferroelectricity has been a central paradigm in multiferroics research. Nevertheless, it was recently shown by density…
We review the phenomenology of coupled magnetic and electric order parameters for systems in which ferroelectric and incommensurate magnetic order occur simultaneously. We discuss the role that such materials might play in fabricating novel…
A metastable perovskite BiFe0.5Sc0.5O3 synthesized under high-pressure (6 GPa) and high- temperature (1500 K) conditions was obtained in two different polymorphs, antipolar Pnma and polar Ima2, through an irreversible behaviour under a…
The design of novel multiferroic ABO$_3$ perovskites is complicated by the presence of necessary magnetic cations and ubiquitous antiferrodistortive modes, both of which suppress polar distortions. Using first-principles simulations, we…
A 20% substitution of Bi with La in the perovskite Bi1-xLaxFe0.5Sc0.5O3 system obtained under high-pressure and high-temperature conditions has been found to induce an incommensurately modulated structural phase. The room temperature X-ray…
Structural behaviour of PbMn$_{7}$O$_{12}$ has been studied by high resolution synchrotron X-ray powder diffraction. This material belongs to a family of quadruple perovskite manganites that exhibit an incommensurate structural modulation…
By means of synchrotron x-ray and electron diffraction, we studied the structural changes at the charge order transition $T_{CO}$=176 K in the mixed-valence quadruple perovskite (NaMn$_3$)Mn$_4$O$_{12}$. Below $T_{CO}$ we find satellite…
It is of great interest to design and make materials in which ferroelectric polarisation is coupled to other order parameters such as lattice, magnetic and electronic instabilities. Such materials will be invaluable in next-generation data…
Recent experimental and theoretical work has shown that the double perovskite NaLaMnWO$_6$ exhibits antiferromagnetic ordering owing to the Mn $d$ states, and computational studies further predict it to exhibit a spontaneous electric…
Magnetically-driven ferroelectric atomic displacements of the order of 10$^{-3} Angstrom have been observed in orthorhombic (perovskite like) YMnO$_3$ by a single-crystal synchrotron x-ray diffraction. The refined polar structure shows the…
Double-perovskite A2BB'O6 oxides with magnetic B and B' ions and E*-type antiferromagnetic order (E*-AFM, i.e. the ++-- structure) are believed to exhibit promising multiferroic properties, and Y2CoMnO6 (YCMO) is one candidate in this…
Incommensurate modulated structure (IMS) in Bi2Sr1.6La0.4CuO6+{\delta} (BSLCO) has been studied by aberration corrected transmission electron microscopy in combination with high-dimensional (HD) space description. Two images in the negative…
In the archetypal antiferroelectric PbZrO3, antiparallel electric dipoles cancel each other, resulting in zero spontaneous polarisation at the macroscopic level. Yet in actual hysteresis loops, the cancellation is rarely perfect and some…
Lead-free antiferroelectric perovskite $\rm AgNbO_3$ is nowadays attracting extensive research interests due to its promising applications in energy storage. Although great progress has been made in optimizing the material performance,…
Commencing from the centrosymmetric MnRMnSbO$_6$ compound, we explore the realm of magnetic polar double-double perovskite oxides characterized by significant ferroelectric polarization. Employing symmetry operations, first-principles…
Inversion-asymmetric antiferromagnets (AFMs) with odd-parity spin-polarization pattern have been proposed as a new venue for spintronics. These AFMs require commensurate ordering to ensure an effective time-reversal symmetry, which…
Ternary cubic perovskite compounds of the form A_(1/3)A'_(1/3)A''_(1/3)BO_3 and AB_(1/3)B'_(1/3)B''_(1/3)O_3, in which the differentiated cations form an alternating series of monolayers, are studied using first-principles methods. Such…
We have determined the magnetic structure of the low-temperature incommensurate phase of multiferroic YMn2O5 using single-crystal neutron diffraction. By employing corepresentation analysis, we have ensured full compliance with both…