Iso-structural phase transition in pyrochlore iridates (Sm _{1-x}$Bix)2Ir2O7(x= 0, 0.02, and 0.10): high-pressure Raman and x-ray diffraction studies.
J Phys Condens Matter
; 36(45)2024 Aug 09.
Article
en En
| MEDLINE
| ID: mdl-39084629
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 â¼20 GPa) and Raman-scattering measurements (up to â¼25 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 Sm2Ir2O7atPcâ¼ 11.2 GPa, associated with the rearrangement of IrO6octahedra in the pyrochlore lattice. The transition pressure decreases to â¼10.2 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.
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Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
J Phys Condens Matter
Asunto de la revista:
BIOFISICA
Año:
2024
Tipo del documento:
Article
País de afiliación:
India
Pais de publicación:
Reino Unido