M Rosalin, K A Irshad, Boby Joseph, Prachi Telang, Surjeet Singh, D V S Muthu, A K Sood
{"title":"Iso-structural phase transition in pyrochlore iridates (Sm _{1-x}$Bi<sub><i>x</i></sub>)<sub>2</sub>Ir<sub>2</sub>O<sub>7</sub>(<i>x</i>= 0, 0.02, and 0.10): high-pressure Raman and x-ray diffraction studies.","authors":"M Rosalin, K A Irshad, Boby Joseph, Prachi Telang, Surjeet Singh, D V S Muthu, A K Sood","doi":"10.1088/1361-648X/ad69ed","DOIUrl":null,"url":null,"abstract":"<p><p>The pyrochlore iridates,<i>A</i><sub>2</sub>Ir<sub>2</sub>O<sub>7</sub>, show a wide variety of structural, electronic, and magnetic properties controlled by the interplay of different exchange interactions, which can be tuned by external pressure. In this work, we report pressure-induced iso-structural phase transitions at ambient temperature using synchrotron-based x-ray diffraction (up to ∼20 GPa) and Raman-scattering measurements (up to ∼25 GPa) of the pyrochlore series (Sm_{1-x}Bi<sub><i>x</i></sub>)<sub>2</sub>Ir<sub>2</sub>O<sub>7</sub>(<i>x</i>= 0, 0.02, and 0.10). Our Raman and x-ray data suggest an iso-structural transition in Sm<sub>2</sub>Ir<sub>2</sub>O<sub>7</sub>atPc∼ 11.2 GPa, associated with the rearrangement of IrO<sub>6</sub>octahedra in the pyrochlore lattice. The transition pressure decreases to ∼10.2 and 9 GPa for<i>x</i>= 0.02 and 0.10, respectively. For all the samples, the linewidth of three phonons associated with Ir-O-Ir (A1gand<i>E<sub>g</sub></i>) and Ir-O (T2g4) vibrations show anomalous decrease up toPc, due to decrease in electron-phonon interaction.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Physics: Condensed Matter","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1088/1361-648X/ad69ed","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, CONDENSED MATTER","Score":null,"Total":0}
引用次数: 0
Abstract
The pyrochlore iridates,A2Ir2O7, show a wide variety of structural, electronic, and magnetic properties controlled by the interplay of different exchange interactions, which can be tuned by external pressure. In this work, we report pressure-induced iso-structural phase transitions at ambient temperature using synchrotron-based x-ray diffraction (up to ∼20 GPa) and Raman-scattering measurements (up to ∼25 GPa) of the pyrochlore series (Sm_{1-x}Bix)2Ir2O7(x= 0, 0.02, and 0.10). Our Raman and x-ray data suggest an iso-structural transition in Sm2Ir2O7atPc∼ 11.2 GPa, associated with the rearrangement of IrO6octahedra in the pyrochlore lattice. The transition pressure decreases to ∼10.2 and 9 GPa forx= 0.02 and 0.10, respectively. For all the samples, the linewidth of three phonons associated with Ir-O-Ir (A1gandEg) and Ir-O (T2g4) vibrations show anomalous decrease up toPc, due to decrease in electron-phonon interaction.
期刊介绍:
Journal of Physics: Condensed Matter covers the whole of condensed matter physics including soft condensed matter and nanostructures. Papers may report experimental, theoretical and simulation studies. Note that papers must contain fundamental condensed matter science: papers reporting methods of materials preparation or properties of materials without novel condensed matter content will not be accepted.