249 citations · 1.2k across the 30 of their papers we have counts for
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Phonon-phonon coupling in bismuth vanadate over a large temperature range across the monoclinic phase
Christina Hill, Georgy Gordeev, Mael Guennou
In this work we study phonon-phonon coupling in bismuth vanadate (BiVO4), known for its second-order transition involving a variety of coupling mechanisms. Using Raman spectroscopy…
Anharmonicity of the antiferrodistortive soft mode in barium zirconate BaZrO
Petter Rosander, Erik Fransson, Cosme Milesi-Brault +6
Barium zirconate (BaZrO) is one of the very few perovskites that is claimed to retain an average cubic structure down to \SI{0}{\K}, while being energetically very close to an…
Birefringence induced by antiferroelectric switching in transparent polycrystalline film
Pranab Parimal Biswas, Cosme Milesi-Brault, Alfredo Blázquez Martínez +7
The most characteristic functional property of antiferroelectric materials is the possibility to induce a phase transition from a non-polar to a polar phase by an electric field. H…
Lattice dynamics and Raman spectrum of supertetragonal PbVO3
Pierre Bouvier, Alireza Sasani, Eric Bousquet +2
Lead vanadate PbVO3 is a polar crystal with a P4mm space group at ambient conditions. It is isostructural with the model soft-mode driven ferroelectric PbTiO3, but differs from it…
Stability of the tetragonal phase of BaZrO3 under high pressure
Constance Toulouse, Danila Amoroso, Robert Oliva +8
In this paper, we revisit the high-pressure behavior of BaZrO3 by a combination of first-principle calculations, Raman spectroscopy, and x-ray diffraction under high pressure. We c…
Patterning enhanced tetragonality in BiFeO3 thin films with effective negative pressure by helium implantation
C. Toulouse, J. Fischer, S. Farokhipoor +13
Helium implantation in epitaxial thin films is a way to control the out-of-plane deformation independently from the in-plane strain controlled by epitaxy. In particular, implantati…
Critical field anisotropy in the antiferroelectric switching of PbZrO3 films
Cosme Milesi-Brault, Nicolas Godard, Stéphanie Girod +6
Antiferroelectrics have been recently sparking interest due to their potential use in energy storage and electrocaloric cooling. Their main distinctive feature is antiferroelectric…
High-contrast imaging of 180° ferroelectric domains by optical microscopy using ferroelectric liquid crystals
Guillaume. F. Nataf, Mael Guennou, Giusy Scalia +3
Ferroelectric liquid crystals (FLCs) couple the direction of their spontaneous electric polarization to the direction of tilt of their optic axis. Consequently, reversal of the ele…
Role of the ferroelastic strain in the optical absorption of BiVO4
Christina Hill, Mads C. Weber, Jannis Lehmann +4
Bismuth vanadate (BiVO4) has recently been under focus for its potential use in photocatalysis thanks to its well-suited absorption edge in the visible light range. Here, we charac…
Imaging of Strain Driven Magnetic Domains and Strong Spin-Phonon Coupling in Epitaxial Thin Films of SrRuO3
Shekhar Tyagi, V. G. Sathe, Gaurav Sharma +3
Epitaxial thin films of SrRuO3 with large strain disorder were grown using pulsed laser deposition method which showed two distinct transition temperatures in Magnetic measurements…
Lattice dynamics and Raman spectrum of BaZrO3 single crystals
Constance Toulouse, Danila Amoroso, Cong Xin +7
BaZrO3 is a perovskite that remains in the simple cubic phase at all temperatures, hence with no first-order Raman-active phonon mode allowed by symmetry. Yet, it exhibits an inten…
Archetypal soft-mode driven antipolar transition in francisite Cu3Bi(SeO3)2O2Cl
Cosme Milesi-Brault, Constance Toulouse, Evan Constable +8
Model materials are precious test cases for elementary theories and provide building blocks for the understanding of more complex cases. Here, we describe the lattice dynamics of t…
Evolution of defect signatures at ferroelectric domain walls in Mg-doped LiNbO3
Guillaume F. Nataf, Mael Guennou, Alexander Haußmann +2
The domain structure of uniaxial ferroelectric lithium niobate single crystals is investigated using Raman spectroscopy mapping. The influence of doping with magnesium and poling a…
Control of surface potential at polar domain walls in a nonpolar oxide
G. F. Nataf, M. Guennou, J. Kreisel +8
Ferroic domain walls could play an important role in microelectronics, given their nanometric size and often distinct functional properties. Until now, devices and device concepts…
Rules and mechanisms governing octahedral tilts in perovskites under pressure
H. J. Xiang, Mael Guennou, Jorge Íñiguez +2
The rotation of octahedra (octahedral tilting) is common in ABO3 perovskites and relevant to many physical phenomena, ranging from electronic and magnetic properties, metal-insulat…
Raman spectroscopy of rare-earth orthoferrites RFeO3 (R = La, Sm, Eu, Gd, Tb, Dy)
Mads Christof Weber, Mael Guennou, Hong Jian Zhao +5
We report a Raman scattering study of six rare earth orthoferrites RFeO3, with R = La, Sm, Eu, Gd, Tb, Dy. The use of extensive polarized Raman scattering of SmFeO3 and first-princ…
Theory of antiferroelectric phase transitions
Pierre Tolédano, Mael Guennou
At variance with structural ferroic phase transitions which give rise to macroscopic tensors coupled to macroscopic fields, criteria defining antiferroelectric (AFE) phase transiti…
Temperature evolution of the band-gap in BiFeO3 traced by resonant Raman scattering
Mads Christof Weber, Mael Guennou, Constance Toulouse +4
Knowledge of the electronic band structure of multiferroic oxides, crucial for the understanding and tuning of photo-induced effects, remains very limited even in the model and tho…
Bismuth-based perovskites as multiferroics
Mael Guennou, Michel Viret, Jens Kreisel
This review devoted to multiferroic properties of Bismuth-based perovskites falls into two parts. The first part focuses on BiFeO3 and summarizes the recent progress made in the st…
Order-Parameter Symmetries of Domain Walls in Ferroelectrics and Ferroelastics
Pierre Tolédano, Mael Guennou, Jens Kreisel
The symmetry of boundaries between ferroelectric, ferroelastic and antiphase domains is a key element for a theoretical understanding of their properties. Here, we derive this symm…
Jahn-Teller, polarity and insulator-to-metal transition in BiMnO3 at high pressure
Mael Guennou, Pierre Bouvier, Pierre Toulemonde +5
The interaction of coexisting structural instabilities in multiferroic materials gives rise to intriguing coupling phenomena and extraordinarily rich phase diagrams, both in bulk m…
Morphotropic interfaces in PMN-PT single crystals
I. Rafalovskyi, M. Guennou, I. Gregora +1
The paper describes heterostructures spontaneously formed in PMN-PT single crystals cooled under bias electric field applied along [001]pc and then zero-field-heated in the vicinit…
High piezoelectric coefficient of single domain Mn-doped NBT-6%BT single crystals
Mael Guennou, Maxim Savinov, Jan Drahokoupil +2
We report a study of properties of Mn-doped NBT-6%BT single crystals. We show that tetragonal single domain states can be stabilized by poling along a [001] direction. For carefull…
Multiple high-pressure phase transitions in BiFeO3
Mael Guennou, Pierre Bouvier, Grace S. Chen +4
We investigate the high-pressure phase transitions in BiFeO3 by single crystal and powder x-ray diffraction, as well as single crystal Raman spectroscopy. Six phase transitions are…