Jens Kreisel
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Jens Kreisel has a total of 32 co-authors. Here are the top co-authors by number of shared publications:
P. Bouvier
Laboratoire d’Electrochimie et de Physicochimie des Matériaux et des Interfaces (CNRS), ENSEEG, BP 75, 38402 St. Martin d’Hères Cedex, France
8 shared publicationsA. Simon
Institut de Chimie de la Matière Condensée de Bordeaux (CNRS), 87 Avenue A. Schweitzer, F-33608 Pessac, France
3 shared publicationsB. Chaabane
Laboratoire des Matériaux et du Génie Physique, ENS de Physique de Grenoble, B.P.46, 38402 St. Martin d’Hères, France
3 shared publicationsB. Dkhil
Laboratoire Structures, Propriétés et Modélisation des Solides, Ecole Centrale Paris, 92290 Châtenay-Malabry, France
3 shared publications- Brahim Dkhil
Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
2 shared publications F. Hippert
Laboratoire des Matériaux et du Génie Physique (CNRS) ENSPG B.P. 46 F-38402 Saint Martin d'Hères Cedex France
2 shared publications
Latest Publications
- Open Access
- 1 March 2008
- Published by EDP Sciences in Reflets de la physique
- No. 8,p. 10-13
Les matériaux multiferroïques
- 1 March 2008
- Published by EDP Sciences in Reflets de la physique
- No. 8,p. 10-13
Open AccessLes matériaux multiferroïques
- 17 July 2006
- Published by American Physical Society (APS) in Physical Review B
- Vol. 74 (1) , 014106
EXAFS study of lead-free relaxor ferroelectricat the ZredgeExtended x-ray absorption fine structure experiments at the Zr edge were carried out on perovskite relaxor ferroelectrics (BTZ) , and on for comparison. Structural information up to around the Zr atoms is obtained, revealing that the local structure differs notably from the average cubic structure deduced from the x-ray diffraction. In particular, our results show that the distance between Zr atoms and their first oxygen neighbors is independent of the Zr substitution rate and equal to that measured in , while the x-ray cubic cell parameter increases linearly with . Furthermore, we show that the Zr atoms tend to segregate in Zr-rich regions. We propose that the relaxor behavior in BTZ could be influenced by the random elastic fields generated by this particular chemical arrangement.- 17 July 2006
- Published by American Physical Society (APS) in Physical Review B
- Vol. 74 (1) , 014106
EXAFS study of lead-free relaxor ferroelectricat the ZredgeExtended x-ray absorption fine structure experiments at the Zr edge were carried out on perovskite relaxor ferroelectrics (BTZ) , and on for comparison. Structural information up to around the Zr atoms is obtained, revealing that the local structure differs notably from the average cubic structure deduced from the x-ray diffraction. In particular, our results show that the distance between Zr atoms and their first oxygen neighbors is independent of the Zr substitution rate and equal to that measured in , while the x-ray cubic cell parameter increases linearly with . Furthermore, we show that the Zr atoms tend to segregate in Zr-rich regions. We propose that the relaxor behavior in BTZ could be influenced by the random elastic fields generated by this particular chemical arrangement.- 4 April 2006
- Published by American Physical Society (APS) in Physical Review B
- Vol. 73 (13) , 132101
Phonon anomalies and the ferroelectric phase transition in multiferroicWe report a temperature-dependent Raman scattering investigation of the multiferroic material bismuth ferrite (BFO). The observed loss of the Raman spectrum at the ferroelectric Curie temperature should be in agreement with a cubic structure of the high-temperature paraelectric phase. Surprisingly, the ferroelectric-to-paraelectric phase transition is not soft-mode driven, indicating a nonconventional ferroelectric. Furthermore, our results reveal pronounced phonon anomalies around the magnetic Néel temperature . We tentatively attribute these anomalies to the multiferroic character of BFO.- 4 April 2006
- Published by American Physical Society (APS) in Physical Review B
- Vol. 73 (13) , 132101
Phonon anomalies and the ferroelectric phase transition in multiferroicWe report a temperature-dependent Raman scattering investigation of the multiferroic material bismuth ferrite (BFO). The observed loss of the Raman spectrum at the ferroelectric Curie temperature should be in agreement with a cubic structure of the high-temperature paraelectric phase. Surprisingly, the ferroelectric-to-paraelectric phase transition is not soft-mode driven, indicating a nonconventional ferroelectric. Furthermore, our results reveal pronounced phonon anomalies around the magnetic Néel temperature . We tentatively attribute these anomalies to the multiferroic character of BFO.- Open Access
EXAFS study of lead-free relaxor ferroelectric BaTi(1-x)Zr(x)O3 at the Zr K-edge
Extended X-ray absorption fine structure (EXAFS) experiments at the Zr K-edge were carried out on perovskite relaxor ferroelectrics BaTi(1-x)Zr(x)O3 (BTZ) (x = 0.25, 0.30, 0.35), and on BaZrO3 for comparison. Structural information up to 4.5 A around the Zr atoms is obtained, revealing that the local structure differs notably from the average Pm-3m cubic structure deduced from X-ray diffraction. In particular, our results show that the distance between Zr atoms and their first oxygen neighbors is independent of the Zr substitution rate x and equal to that measured in BaZrO3, while the X-ray cubic cell parameter increases linearly with x. Furthermore, we show that the Zr atoms tend to segregate in Zr-rich regions. We propose that the relaxor behavior in BTZ is linked to random elastic fields generated by this particular chemical arrangement, rather than to random electric fields as is the case in most relaxors.
Open AccessEXAFS study of lead-free relaxor ferroelectric BaTi(1-x)Zr(x)O3 at the Zr K-edge
Extended X-ray absorption fine structure (EXAFS) experiments at the Zr K-edge were carried out on perovskite relaxor ferroelectrics BaTi(1-x)Zr(x)O3 (BTZ) (x = 0.25, 0.30, 0.35), and on BaZrO3 for comparison. Structural information up to 4.5 A around the Zr atoms is obtained, revealing that the local structure differs notably from the average Pm-3m cubic structure deduced from X-ray diffraction. In particular, our results show that the distance between Zr atoms and their first oxygen neighbors is independent of the Zr substitution rate x and equal to that measured in BaZrO3, while the X-ray cubic cell parameter increases linearly with x. Furthermore, we show that the Zr atoms tend to segregate in Zr-rich regions. We propose that the relaxor behavior in BTZ is linked to random elastic fields generated by this particular chemical arrangement, rather than to random electric fields as is the case in most relaxors.
- Open Access
Colossal Spin-Phonon Anomalies and the Ferroelectric Phase Transition in the Model Multiferroic Bifeo3
We report a temperature-dependent Raman and neutron scattering investigation of the multiferroic material bismuth ferrite BiFeO3 (BFO).
Open AccessColossal Spin-Phonon Anomalies and the Ferroelectric Phase Transition in the Model Multiferroic Bifeo3
We report a temperature-dependent Raman and neutron scattering investigation of the multiferroic material bismuth ferrite BiFeO3 (BFO).
- 29 October 2004
- Published by American Physical Society (APS) in Physical Review B
- Vol. 70 (13) , 134114
Effect of high pressure on the solid solution: A Raman scattering investigationWe report a high-pressure Raman scattering investigation of , which is considered as a prototype relaxor-based piezoelectric. The observed spectral changes are important and it is the pressure-induced appearance of a sharp band at roughly for all investigated , that allows the construction of a partial phase diagram which is characterized by a high-pressure non-cubic structure. This high-pressure structure is very similar if not identical to the high-pressure structure of PMN. Finally, we present a discussion of the high-wavenumber part of the Raman spectrum in terms of a two-mode behavior, which suggests a very local order around Ti atoms.- 29 October 2004
- Published by American Physical Society (APS) in Physical Review B
- Vol. 70 (13) , 134114
Effect of high pressure on the solid solution: A Raman scattering investigationWe report a high-pressure Raman scattering investigation of , which is considered as a prototype relaxor-based piezoelectric. The observed spectral changes are important and it is the pressure-induced appearance of a sharp band at roughly for all investigated , that allows the construction of a partial phase diagram which is characterized by a high-pressure non-cubic structure. This high-pressure structure is very similar if not identical to the high-pressure structure of PMN. Finally, we present a discussion of the high-wavenumber part of the Raman spectrum in terms of a two-mode behavior, which suggests a very local order around Ti atoms.- 6 May 2004
- Published by Wiley in physica status solidi (c)
- Vol. 1 (7) , 1679-1682
Synthesis and characterization of SmNiO 3 thin films
- 6 May 2004
- Published by Wiley in physica status solidi (c)
- Vol. 1 (7) , 1679-1682
Synthesis and characterization of SmNiO 3 thin films
- 17 March 2004
- Published by American Physical Society (APS) in Physical Review B
- Vol. 69 (9) , 092104
High-pressure Raman investigation of the Pb-free relaxorWe report high-pressure Raman measurements (up to 27 GPa) on the perovskite-type relaxor ferroelectric Distinct changes of the Raman spectra with increasing pressure illustrate that presents important pressure instabilities leading to at least two phase transitions around 5.7 GPa and 15.1 GPa, respectively. The observed pressure-induced spectral changes for are reminiscent of features that have been observed for pure thus for a classic ferroelectric. The latter is surprising since earlier reports indicate a relaxor-characteristic Raman signature as a function of temperature, thus illustrating that might well occupy a peculiar niche in perovskite-type ferroelectrics.- 17 March 2004
- Published by American Physical Society (APS) in Physical Review B
- Vol. 69 (9) , 092104
High-pressure Raman investigation of the Pb-free relaxorWe report high-pressure Raman measurements (up to 27 GPa) on the perovskite-type relaxor ferroelectric Distinct changes of the Raman spectra with increasing pressure illustrate that presents important pressure instabilities leading to at least two phase transitions around 5.7 GPa and 15.1 GPa, respectively. The observed pressure-induced spectral changes for are reminiscent of features that have been observed for pure thus for a classic ferroelectric. The latter is surprising since earlier reports indicate a relaxor-characteristic Raman signature as a function of temperature, thus illustrating that might well occupy a peculiar niche in perovskite-type ferroelectrics.- 29 July 2003
- Published by American Physical Society (APS) in Physical Review B
- Vol. 68 (1) , 014113
High-pressure x-ray scattering of oxides with a nanoscale local structure: Application toMany of the outstanding properties in oxides are related to materials with an intrinsic nanoscaled local structure, where the different regions are characterized by competing chemical, structural, and/or physical properties. One of the major challenges in the analysis of the nanoscaled oxides is experimental access to the local properties, which is often at best a difficult task, a fact that often inhibits the understanding of properties such as colossal magnetoresistance, giant piezoelectricity, and high-temperature superconductivity. Here we present an investigation of the relaxor ferroelectric considered as a model type of nanostructured oxide, by combining the parameter high-pressure with x-ray diffuse scattering. We show that nanoscaled characteristics can be investigated in detail by combining such measurements with simulation of different diffuse scattering models. We observe two distinct structural disorders, one of which is characterized by the observation of asymmetric diffuse scattering in perovskites due to planar polar defects.- 29 July 2003
- Published by American Physical Society (APS) in Physical Review B
- Vol. 68 (1) , 014113
High-pressure x-ray scattering of oxides with a nanoscale local structure: Application toMany of the outstanding properties in oxides are related to materials with an intrinsic nanoscaled local structure, where the different regions are characterized by competing chemical, structural, and/or physical properties. One of the major challenges in the analysis of the nanoscaled oxides is experimental access to the local properties, which is often at best a difficult task, a fact that often inhibits the understanding of properties such as colossal magnetoresistance, giant piezoelectricity, and high-temperature superconductivity. Here we present an investigation of the relaxor ferroelectric considered as a model type of nanostructured oxide, by combining the parameter high-pressure with x-ray diffuse scattering. We show that nanoscaled characteristics can be investigated in detail by combining such measurements with simulation of different diffuse scattering models. We observe two distinct structural disorders, one of which is characterized by the observation of asymmetric diffuse scattering in perovskites due to planar polar defects.- 1 July 2003
- Published by Wiley in Journal of Raman Spectroscopy
- Vol. 34 (7-8) , 524-531
High‐pressure Raman spectroscopy of nano‐structured ABO3 perovskites: a case study of relaxor ferroelectrics
A large number of outstanding physical properties observed in perovskite‐type oxides, such as giant piezoelectricity, colossal magneto‐resistance and high‐Tc superconductivity, are related to an intrinsic nano‐scaled local structure. For instance, the presence of a nano‐scaled structure is characteristic of so‐called relaxor ferroelectrics (relaxors), which have attracted considerable attention since the recent discovery of ultra‐high strain and giant piezoelectric properties. In this paper we review, through a case study of relaxors, how the combination of the external parameter high‐pressure and Raman spectroscopy allows an instructive investigation of nano‐scaled perovskites, which is often at best a difficult task for conventional ‘average‐structure’ techniques such as diffraction. We show that perovskite‐type relaxors present important pressure instabilities with respect to both cation sizes and we suggest that the latter instabilities might well be at the origin of the reduced dielectric performances that are observed for strained thin‐film relaxors. Finally, we briefly illustrate how the approach might be used for nano‐scaled manganite‐type oxides. Copyright © 2003 John Wiley & Sons, Ltd.
- 1 July 2003
- Published by Wiley in Journal of Raman Spectroscopy
- Vol. 34 (7-8) , 524-531
High‐pressure Raman spectroscopy of nano‐structured ABO3 perovskites: a case study of relaxor ferroelectrics
A large number of outstanding physical properties observed in perovskite‐type oxides, such as giant piezoelectricity, colossal magneto‐resistance and high‐Tc superconductivity, are related to an intrinsic nano‐scaled local structure. For instance, the presence of a nano‐scaled structure is characteristic of so‐called relaxor ferroelectrics (relaxors), which have attracted considerable attention since the recent discovery of ultra‐high strain and giant piezoelectric properties. In this paper we review, through a case study of relaxors, how the combination of the external parameter high‐pressure and Raman spectroscopy allows an instructive investigation of nano‐scaled perovskites, which is often at best a difficult task for conventional ‘average‐structure’ techniques such as diffraction. We show that perovskite‐type relaxors present important pressure instabilities with respect to both cation sizes and we suggest that the latter instabilities might well be at the origin of the reduced dielectric performances that are observed for strained thin‐film relaxors. Finally, we briefly illustrate how the approach might be used for nano‐scaled manganite‐type oxides. Copyright © 2003 John Wiley & Sons, Ltd.