M. Gajek, M. Bibes, J. Fontcuberta, A. Barthélémy, and A. Fert, Tunnel junctions with multiferroic barriers, Nature Materials, vol.85, issue.4, p.296, 2007.
DOI : 10.1038/nmat1860

:. F. Yang, M. H. Tang, Z. Ye, and Y. C. Zhou, Eight logic states of tunneling magnetoelectroresistance in multiferroic tunnel junctions, Journal of Applied Physics, vol.102, issue.4, p.44504, 2007.
DOI : 10.1063/1.2768075

:. M. Bibes and A. Barthélémy, Multiferroics: Towards a magnetoelectric memory, Nature Materials, vol.43, issue.6, p.425, 2008.
DOI : 10.1038/nmat2189

:. R. Nelmes, Structural studies of boracites. A review of the properties of boracites, Journal of Physics C: Solid State Physics, vol.7, issue.21, p.3840, 1974.
DOI : 10.1088/0022-3719/7/21/008

:. G. Samara and J. F. Scott, Dielectric anomalies in BaMnF4 at low temperatures, Solid State Communications, vol.21, issue.2, p.167, 1977.
DOI : 10.1016/0038-1098(77)90675-5

:. M. Fiebig, Revival of the magnetoelectric effect, Journal of Physics D: Applied Physics, vol.38, issue.8, pp.123-154, 1960.
DOI : 10.1088/0022-3727/38/8/R01

:. R. Coehlo, Physics of dielectrics for engineer, 1979.

:. B. Jaffe, W. R. Cook, and H. Jaffe, Piezoelectric Ceramics, Journal of the American Ceramic Society, vol.36, issue.11, 1971.
DOI : 10.1143/JPSJ.7.333

:. J. Valasek, Piezo-Electric and Allied Phenomena in Rochelle Salt, Physical Review, vol.17, issue.4, p.475, 1921.
DOI : 10.1103/PhysRev.17.475

:. B. Matthias, New Ferroelectric Crystals, Physical Review, vol.75, issue.11, p.1771, 1949.
DOI : 10.1103/PhysRev.75.1771

:. A. Devonshire, Theory of ferroelectrics, Advances in Physics, vol.74, issue.10, p.85, 1954.
DOI : 10.1103/PhysRev.80.1106

:. P. Tolédano and J. C. Tolédano, Order-parameter symmetries for the phase transitions of nonmagnetic secondary and higher-order ferroics, Physical Review B, vol.16, issue.1, p.386, 1977.
DOI : 10.1103/PhysRevB.16.386

:. M. Glazer, The classification of tilted octahedra in perovskites, Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, vol.28, issue.11, p.3384, 1972.
DOI : 10.1107/S0567740872007976

:. J. Sakurai, R. A. Cowley, G. Dolling, and J. , Crystal Dynamics and the Ferroelectric Phase Transition of Sodium Nitrite, Journal of the Physical Society of Japan, vol.28, issue.6, p.1426, 1970.
DOI : 10.1143/JPSJ.28.1426

:. W. Cochran, Crystal stability and the theory of ferroelectricity, Advances in Physics, vol.44, issue.36, p.387, 1960.
DOI : 10.1039/tf9494500155

:. W. Cochran, Crystal stability and the theory of ferroelectricity part II. Piezoelectric crystals, Advances in Physics, vol.13, issue.40, p.401, 1961.
DOI : 10.1103/PhysRev.119.980

:. G. Shirane, B. C. Frazer, and V. J. Minkievitz, Soft Optic Modes in Barium Titanate, Physical Review Letters, vol.19, issue.5, p.234, 1967.
DOI : 10.1103/PhysRevLett.19.234

:. J. Axe, J. Harada, and G. Shirane, Anomalous Acoustic Dispersion in Centrosymmetric Crystals with Soft Optic Phonons, Physical Review B, vol.1, issue.3, p.1227, 1970.
DOI : 10.1103/PhysRevB.1.1227

:. R. Comès, M. Lambert, and A. Guinier, The chain structure of BaTiO3 and KNbO3, Solid State Communications, vol.6, issue.10, p.715, 1968.
DOI : 10.1016/0038-1098(68)90571-1

:. H. Takahashi and J. , A Note on the Theory of Barium Titanate, Journal of the Physical Society of Japan, vol.16, issue.9, p.1685, 1961.
DOI : 10.1143/JPSJ.16.1685

:. I. Bersuker, On the origin of ferroelectricity in perovskite-type crystals, Physics Letters, vol.20, issue.6, p.589, 1966.
DOI : 10.1016/0031-9163(66)91127-9

:. G. Burns and F. , Glassy polarization behavior in ferroelectric compounds and, Solid State Communications, vol.48, issue.10, p.853, 1983.
DOI : 10.1016/0038-1098(83)90132-1

:. G. Fulcher and J. Am, ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES, Journal of the American Ceramic Society, vol.8, issue.6, p.339, 1925.
DOI : 10.1111/j.1151-2916.1925.tb16731.x

:. A. Bokov and Z. G. Ye, Recent progress in relaxor ferroelectrics with perovskite structure, Journal of Materials Science, vol.45, issue.156, p.31, 2006.
DOI : 10.1007/s10853-005-5915-7

:. G. Samara, perovskites, Journal of Physics: Condensed Matter, vol.15, issue.9, p.367, 2003.
DOI : 10.1088/0953-8984/15/9/202

:. J. Nye, Physical properties in crystals, 1957.

:. K. Aizu and J. , Possible Species of ???Ferroelastic??? Crystals and of Simultaneously Ferroelectric and Ferroelastic Crystals, Journal of the Physical Society of Japan, vol.27, issue.2, p.387, 1969.
DOI : 10.1143/JPSJ.27.387

:. K. Aizu, Possible Species of Ferromagnetic, Ferroelectric, and Ferroelastic Crystals, Physical Review B, vol.2, issue.3, p.754, 1970.
DOI : 10.1103/PhysRevB.2.754

:. R. Newnham and L. E. Cross, Symmetry of secondary ferroics. I, Materials Research Bulletin, vol.9, issue.7, p.927, 1974.
DOI : 10.1016/0025-5408(74)90172-X

:. R. Newnham and L. E. Cross, Symmetry of secondary ferroics. II, Materials Research Bulletin, vol.9, issue.8, p.1021, 1974.
DOI : 10.1016/0025-5408(74)90012-9

:. E. Bertaut and M. Mercier, Magnetoelectricity in theory and experiment, Materials Research Bulletin, vol.6, issue.10, p.907, 1971.
DOI : 10.1016/0025-5408(71)90069-9

:. E. Bertaut and M. Mercier, Magnetoelectricity in theory and experiment, Materials Research Bulletin, vol.6, issue.10, p.907, 1971.
DOI : 10.1016/0025-5408(71)90069-9

:. S. Shtrikman and J. Treves, Powders, Physical Review, vol.130, issue.3, p.986, 1963.
DOI : 10.1103/PhysRev.130.986

:. E. Asher, H. Rieder, H. Schmid, and H. Stössel, I, Journal of Applied Physics, vol.37, issue.3, p.1404, 1966.
DOI : 10.1063/1.1708493

:. W. Brown, R. M. Hornreich, and S. Shtrikman, Upper Bound on the Magnetoelectric Susceptibility, Physical Review, vol.168, issue.2, p.574, 1968.
DOI : 10.1103/PhysRev.168.574

:. B. Aken, T. T. Palstra, A. Filippetti, and N. , The origin of ferroelectricity in magnetoelectric YMnO3, Nature Materials, vol.3, issue.3, p.164, 2004.
DOI : 10.1038/nmat1080

:. R. Ramesh and N. A. Spaldin, Multiferroics: progress and prospects in thin films, Nature Materials, vol.2, issue.1, p.21, 2007.
DOI : 10.1038/nmat1805

:. G. Bokij, The Theory of Daltonides and Bertollides, disponible sur internet, Zhurn. Neorganich. Khim, issue.2, pp.22-30, 1977.

:. F. Koch and M. E. Fine, O as Related to the Defect Structure, Journal of Applied Physics, vol.38, issue.3, p.1470, 1967.
DOI : 10.1063/1.1709672

:. S. Anderson, B. Colen, U. Kuylenstierna, and A. Magnéli, Phase Analysis Studies on the Titanium-Oxygen System., Acta Chemica Scandinavica, vol.11, p.1641, 1957.
DOI : 10.3891/acta.chem.scand.11-1641

:. J. Anderson and J. , Equilibria of intermediate oxides in the titanium-oxygen system, Journal of the Less Common Metals, vol.22, issue.2, p.219, 1970.
DOI : 10.1016/0022-5088(70)90022-6

:. J. Anderson and R. Burch, Lattice energies and heats of formation of the TinO2n???1 shear phases, Journal of Physics and Chemistry of Solids, vol.32, issue.5, p.923, 1971.
DOI : 10.1016/S0022-3697(71)80337-2

:. D. Vandeven, J. Galy, M. Pouchard, and P. Hagenmuller, Evolution structurale en fonction de la temperature de quelques bronzes oxygenes de tungstene pauvres en element d'insertion, Materials Research Bulletin, vol.2, issue.8, p.809, 1967.
DOI : 10.1016/0025-5408(67)90008-6

URL : https://hal.archives-ouvertes.fr/hal-00135081

:. E. Banks and G. Goldstein, The solution of lithium in hexagonal potassium tungsten bronze, Inorganic Chemistry, vol.7, issue.5, p.966, 1968.
DOI : 10.1021/ic50063a024

:. A. Magnéli, Studies on the Hexagonal Tungsten Bronzes of Potassium, Rubidium, and Cesium., Acta Chemica Scandinavica, vol.7, p.315, 1953.
DOI : 10.3891/acta.chem.scand.07-0315

:. V. Bovtun, S. Kamba, S. Veljko, M. Savinov, and J. Petzelt, Relaxor-like behavior of lead-free Sr2LaTi2Nb3O15 ceramics with tetragonal tungsten bronze structure, Journal of Applied Physics, vol.101, issue.5, p.54115, 2007.
DOI : 10.1063/1.2713094

:. M. Lundberg, M. Sunberg, and A. Magnéli, The ???pentagonal column??? as a building unit in crystal and defect structures of some groups of transition metal compounds, Journal of Solid State Chemistry, vol.44, issue.1, p.32, 1982.
DOI : 10.1016/0022-4596(82)90398-X

:. P. Labbe, Tungsten Oxides, Tungsten Bronzes and Tungsten Bronze-Type Structures, Key Engineering Materials, vol.68, p.293, 1992.
DOI : 10.4028/www.scientific.net/KEM.68.293

:. A. Simon and J. Ravez, Solid-state chemistry and??non-linear properties of??tetragonal tungsten bronzes materials, Comptes Rendus Chimie, vol.9, issue.10, p.1268, 2006.
DOI : 10.1016/j.crci.2006.04.001

URL : https://hal.archives-ouvertes.fr/hal-00096836

:. T. Gier, D. G. Pease, A. W. Sleight, and T. A. Bither, New lithium, ammonium, and tin hexagonal tungsten bronzes prepared hydrothermallly, Inorganic Chemistry, vol.7, issue.8, p.1646, 1968.
DOI : 10.1021/ic50066a036

:. B. Chamberland, Preparation of bronzes by an alkali azide-metal oxide reaction, Inorganic Chemistry, vol.8, issue.5, p.1183, 1969.
DOI : 10.1021/ic50075a032

:. M. Pouchard, J. P. Chaminade, J. P. Doumerc, J. C. Launay, and P. Hagenmuller, Sur quelques bronzes oxygenes de tungstene CoxWO3 et NixWO3, Materials Research Bulletin, vol.7, issue.3, p.223, 1972.
DOI : 10.1016/0025-5408(72)90240-1

:. J. Ravez, A. Perron, and J. P. Chaminade, Etude des propri??t??s cristallographiques, di??lectriques et d'optique non lin??aire de quelques nouvelles phases de composition BaxLi5???2xNb5(1???y)Ta5yO15 et de structure bronzes oxyg??n??s de tungst??ne quadratiques, Journal of Solid State Chemistry, vol.10, issue.3, p.274, 1974.
DOI : 10.1016/0022-4596(74)90035-8

:. M. Francombe and B. Lewis, Structural, dielectric and optical properties of ferroelectric lead metaniobate, Acta Crystallographica, vol.11, issue.10, p.696, 1958.
DOI : 10.1107/S0365110X58001882

:. S. Abrahams, S. K. Kurtz, and P. B. Jamieson, Atomic Displacement Relationship to Curie Temperature and Spontaneous Polarization in Displacive Ferroelectrics, Physical Review, vol.172, issue.2, p.551, 1969.
DOI : 10.1103/PhysRev.172.551

:. J. Ravez, J. P. Budin, and P. Hagenmuller, Etude comparative des propri??t??s cristallographiques, di??lectriques et d'optique non lin??aire des phases ABCNb5O15 (A = Ca, Sr, Ba, B = Ca, Sr, Ba, C = Na, K) de type ???bronzes oxyg??n??s de tungst??ne quadratiques???, Journal of Solid State Chemistry, vol.5, issue.2, p.239, 1972.
DOI : 10.1016/0022-4596(72)90034-5

:. M. Pouchard, J. P. Chaminade, and A. Perron, Influence de divers types de substitutions cationiques sur les propri??t??s di??lectriques de niobates de structure ???bronzes oxyg??n??s de tungst??ne quadratiques???, Journal of Solid State Chemistry, vol.14, issue.3, p.274, 1975.
DOI : 10.1016/0022-4596(75)90032-8

:. J. Nakano and T. Yamada, Ferroelectric and optical properties of lead potassium niobate, Journal of Applied Physics, vol.46, issue.6, p.2361, 1975.
DOI : 10.1063/1.321914

:. J. Schneck and F. Denoyer, Incommensurate phases in barium sodium niobate, Physical Review B, vol.23, issue.1, p.383, 1981.
DOI : 10.1103/PhysRevB.23.383

:. J. Ravez, S. C. Abrahams, and R. De-pape, and the phase transition at 490 K, Journal of Applied Physics, vol.65, issue.10, p.3987, 1989.
DOI : 10.1063/1.343369

:. R. Blinc, G. Tav?ar, B. ?emva, and D. Han?el, Weak ferromagnetism and ferroelectricity in K3Fe5F15, Journal of Applied Physics, vol.103, issue.7, p.74114, 2008.
DOI : 10.1063/1.2903525

:. B. Scott, E. A. Giess, G. Burns, and D. F. O-'kane, Alkali-rare earth niobates with the tungsten bronze-type structure, Materials Research Bulletin, vol.3, issue.10, p.831, 1968.
DOI : 10.1016/0025-5408(68)90100-1

:. J. Haussonne, Traité des matériaux T.16 céramiques et verres: principe et techniques d'élaboration, Presse polytechniques et universitaires romanes, 2005.

:. S. Geller and M. A. Gilleo, The crystal structure and ferrimagnetism of yttrium-iron garnet, Y3Fe2(FeO4)3, Journal of Physics and Chemistry of Solids, vol.3, issue.1-2, p.30, 1957.
DOI : 10.1016/0022-3697(57)90044-6

:. P. Caro, J. O. Sawyer, and L. Eyring, The infrared spectra of rare earth carbonates, Spectrochimica Acta Part A: Molecular Spectroscopy, vol.28, issue.6, p.1167, 1972.
DOI : 10.1016/0584-8539(72)80088-6

:. S. Bernal, J. A. Diaz, and R. Garcia, Study of some aspects of the reactivity of La2O3 with CO2 and H2O, Journal of Materials Science, vol.74, issue.2, p.537, 1985.
DOI : 10.1007/BF01026524

:. S. Bernal, G. Blanco, and J. A. Gatica, Chemical reactivity of binary rare earth oxides in Binary Rare Earth Oxides, Z. Zang, p.9, 2004.

:. K. Martirosyan, N. S. Martirosyan, and A. E. Chalykh, Doping of Hard-Magnetic Ferrites, Inorganic Materials, vol.40, issue.5, p.527, 2004.
DOI : 10.1023/B:INMA.0000027601.25937.82

:. W. Lixi, H. Qiang, and M. Lei, Influence of Sm3+ Substitution on Microwave Magnetic Performance of Barium Hexaferrites, Journal of Rare Earths, vol.25, p.216, 2007.
DOI : 10.1016/S1002-0721(07)60473-6

:. J. Schneck and F. Denoyer, Incommensurate phases in barium sodium niobate, Physical Review B, vol.23, issue.1, p.383, 1981.
DOI : 10.1103/PhysRevB.23.383

:. J. Schneck, J. C. Tolédano, and G. Errandonea, Coexistence of two phases in incommensurate barium sodium niobate, Phase Transitions, vol.24, issue.4, p.359, 1987.
DOI : 10.1002/pssa.2210920103

:. V. Bovtun, S. Kamba, S. Veljko, M. Savinov, and J. Petzelt, Relaxor-like behavior of lead-free Sr2LaTi2Nb3O15 ceramics with tetragonal tungsten bronze structure, Journal of Applied Physics, vol.101, issue.5, p.54115, 2007.
DOI : 10.1063/1.2713094

:. M. Glazer, The classification of tilted octahedra in perovskites, Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, vol.28, issue.11, p.3384, 1972.
DOI : 10.1107/S0567740872007976

:. R. Roth and J. Res, Phase equilibrium relations in the binary system lead oxide-niobium pentoxide, Journal of Research of the National Bureau of Standards, vol.62, issue.1, p.27, 1959.
DOI : 10.6028/jres.062.006

:. M. Venet, J. C. M-'peko, and F. L. Zapotto, Dynamics of normal to diffuse and relaxor phase transition in lead metaniobate-based ferroelectric ceramics, Applied Physics Letters, vol.94, issue.17, p.172901, 2009.
DOI : 10.1063/1.3122149

V. B. De-tantale and .. , 1.2 Mesures diélectriques, évolution de T c avec l'ajout, p.172

S. Bovtun, S. Kamba, M. Veljko, J. Savinov, and . Petzelt, Relaxor-like behavior of lead-free Sr2LaTi2Nb3O15 ceramics with tetragonal tungsten bronze structure, Références bibliographiques, p.54115, 2007.
DOI : 10.1063/1.2713094

:. B. Woo and B. K. Kim, Effects of Niobium Addition on the Relaxor Ferroelectric Properties and Ordering Structures of Lead Iron Tantalates, Japanese Journal of Applied Physics, vol.42, issue.Part 1, No. 9B, p.6037, 2003.
DOI : 10.1143/JJAP.42.6037

:. C. Elissalde, A. Villesuzanne, J. Ravez, and M. Pouchard, Correlations between curie temperature, relaxation frequency and chemical bonding in relaxor ferroelectric materials, Ferroelectrics, vol.38, issue.1, p.131, 1997.
DOI : 10.1021/ic00141a005

:. J. Ravez, C. Broustéra, and A. Simon, Lead-free ferroelectric relaxor ceramics in the BaTiO3-BaZrO3-CaTiO3 system, Journal of Materials Chemistry, vol.9, issue.7, p.1609, 1999.
DOI : 10.1039/a902335f

:. A. Simon, J. Ravez, and M. Maglione, The crossover from a ferroelectric to a relaxor state in lead-free solid solutions, Journal of Physics: Condensed Matter, vol.16, issue.6, p.963, 2004.
DOI : 10.1088/0953-8984/16/6/023

URL : https://hal.archives-ouvertes.fr/hal-00136253

:. A. Simon, J. Ravez, and M. Maglione, Relaxor properties of Ba0.9Bi0.067(Ti1???xZrx)O3 ceramics, Solid State Sciences, vol.7, issue.8, p.925, 2005.
DOI : 10.1016/j.solidstatesciences.2005.04.009

URL : https://hal.archives-ouvertes.fr/hal-00015537

:. J. Kreisel, A. M. Glazer, P. Bouvier, and G. Lucazeau, perovskite, Physical Review B, vol.63, issue.17, p.174106, 2001.
DOI : 10.1103/PhysRevB.63.174106

URL : https://hal.archives-ouvertes.fr/hal-01067349

:. G. Fulcher, ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES, Journal of the American Ceramic Society, vol.8, issue.6, p.339, 1925.
DOI : 10.1111/j.1151-2916.1925.tb16731.x

:. D. Viehland, S. J. Jang, L. E. Cross, and M. Wuttig, Freezing of the polarization fluctuations in lead magnesium niobate relaxors, Journal of Applied Physics, vol.68, issue.6, p.2916, 1990.
DOI : 10.1063/1.346425

:. R. Comès, M. Lambert, and A. Guinier, The chain structure of BaTiO3 and KNbO3, Solid State Communications, vol.6, issue.10, p.715, 1968.
DOI : 10.1016/0038-1098(68)90571-1

V. .. De-ttb-niobates-ba, . Vii, and .. Introduction, 211 VII

:. R. Brandt and H. Mueller-buschbaum, The crystal chemistry of the tetragonal tungsten-bronze: Ba6FeNb9O30, Monatshefte f???r Chemie Chemical Monthly, vol.4, issue.11, p.1239, 1986.
DOI : 10.1007/BF00810868

:. T. Debnath, S. C. Roy, C. H. Rüscher, and A. Hussain, Synthesis and characterization of niobium-doped potassium tetragonal tungsten bronzes, K x Nb y W1???y O3, Journal of Materials Science, vol.2008, issue.1, p.179, 2009.
DOI : 10.1007/s10853-008-3101-4

:. A. Boudou and J. Sapriel, and related crystals, Physical Review B, vol.21, issue.1, p.61, 1980.
DOI : 10.1103/PhysRevB.21.61

:. W. Haidinger, XIX. Description of Fergusonite, a New Mineral Species, Transactions of the Royal Society of Edinburgh, vol.10, issue.02, p.271, 1826.
DOI : 10.1017/S0080456800024327

:. V. Hartwell, Kongliga Svenska Vetenskaps-Akademiens Handlingar, p.167, 1828.

:. S. Tsunekawa, T. Kamiyama, and H. Asano, Relationship between Covalence and Displacive Phase Transition Temperature in RAO4 and LiAO3 (R = Rare-Earth Element and A = Nb and Ta), Journal of Solid State Chemistry, vol.116, issue.1, p.28, 1995.
DOI : 10.1006/jssc.1995.1177

:. N. Toma?i?, A. Gajovi?, and V. Bermanec, Recrystallization mechanisms of fergusonite from metamict mineral precursors, Physics and Chemistry of Minerals, vol.12, issue.60, p.145, 2006.
DOI : 10.1007/s00269-006-0061-6