Dielectric relaxations in SrTiO_3 doped with La_2O_3 and MnO_2 at low temperatures Export

@article{citeulike:780694, abstract = {In addition to the dielectric relaxation around 170 K in the cubic structure of Sr\_{1–3x/2}La\_x TiO\_3, a similar relaxation was observed at about 70 K in the tetragonal structure with an activation energy in the range 0.13–0.16 eV which increases as x in Sr\_{1–3x/2}La\_x TiO\_3 varies from 0.60–3.00 at\%. This relaxation is explained by Skanavi's model and is discussed in terms of thermal motions of Ti^{4+} between potential minima produced by lattice distortions in the tetragonal structure. In order to provide a direct evidence for the suggestion that the dielectric relaxation around 170 K in the cubic is due to thermal motions of Ti^{4+}, dielectric properties on manganese-doped specimens, Sr\_{1–3x/2}La\_x Mn\_y Ti\_{1–y} ),O\_3 with x=1.40×10^{–2} and y=0.1×10^{–2}, were investigated because Mn4+ substitutes for Ti4+. As well as the relaxation due to Ti4+, this specimen exhibits another peak due to Mn4+ with an activation energy somewhat smaller than that of Ti4+. The activation energies and the relative intensity of these relaxation processes are explained by the difference in ionic radii of Mn^{4+} and Ti^{4+} and the difference in formation energies of a strontium vacancy adjacent to Mn^{4+} and that to Ti^{4+}, which were calculated theoretically using a shell model.}, author = {Iguchi, E. and Lee, K. J.}, citeulike-article-id = {780694}, citeulike-linkout-0 = {http://dx.doi.org/10.1007/BF00365185}, doi = {10.1007/BF00365185}, keywords = {dielectric, relaxation, slto, sto}, pages = {5809+}, posted-at = {2006-07-31 07:41:29}, priority = {2}, title = {Dielectric relaxations in SrTiO\_3 doped with La\_2O\_3 and MnO\_2 at low temperatures}, url = {http://dx.doi.org/10.1007/BF00365185}, volume = {28}, year = {1993} }

TY - JOUR ID - citeulike:780694 L3 - citeulike-article-id:780694 N2 - In addition to the dielectric relaxation around 170 K in the cubic structure of Sr_{1–3x/2}La_x TiO_3, a similar relaxation was observed at about 70 K in the tetragonal structure with an activation energy in the range 0.13–0.16 eV which increases as x in Sr_{1–3x/2}La_x TiO_3 varies from 0.60–3.00 at%. This relaxation is explained by Skanavi's model and is discussed in terms of thermal motions of Ti^{4+} between potential minima produced by lattice distortions in the tetragonal structure. In order to provide a direct evidence for the suggestion that the dielectric relaxation around 170 K in the cubic is due to thermal motions of Ti^{4+}, dielectric properties on manganese-doped specimens, Sr_{1–3x/2}La_x Mn_y Ti_{1–y} ),O_3 with x=1.40×10^{–2} and y=0.1×10^{–2}, were investigated because Mn4+ substitutes for Ti4+. As well as the relaxation due to Ti4+, this specimen exhibits another peak due to Mn4+ with an activation energy somewhat smaller than that of Ti4+. The activation energies and the relative intensity of these relaxation processes are explained by the difference in ionic radii of Mn^{4+} and Ti^{4+} and the difference in formation energies of a strontium vacancy adjacent to Mn^{4+} and that to Ti^{4+}, which were calculated theoretically using a shell model. TI - Dielectric relaxations in SrTiO_3 doped with La_2O_3 and MnO_2 at low temperatures VL - 28 SP - 5809 KW - dielectric KW - relaxation KW - slto KW - sto AU - Iguchi, E AU - Lee, KJ PY - 1993/// UR - http://dx.doi.org/10.1007/BF00365185 ER -