Local symmetry breaking and spin-phonon coupling in SmCrO3 orthochromite

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:361

Article

El Amrani, M.¹  Zaghrioui, M.¹  Ta Phuoc, V.¹  Gervais, F.¹  Massa, Nestor E.² 

[1] Univ Tours, IUT Blois, GREMAN CNRS UMR 7347, F-41029 Blois, France

[2] Natl Univ La Plata, Lab Nacl Invest & Serv Espect Opt, Ctr CEQUINOR, RA-1900 La Plata, Buenos Aires, Argentina

关键词: Multiferroic;    Orthochromite;    Raman scattering;    Infrared reflectivity;   

DOI  :  10.1016/j.jmmm.2014.02.057

来源: Elsevier

【 摘 要 】

Raman scattering and infrared reflectivity performed on polycrystalline SmCrO3 support strong influence of the antiferromagnetic order on phonon modes. Both measurements show softening of some modes below T-N. Such a behavior is explained by spin phonon coupling in this compound. Furthermore, temperature dependence of the infrared spectra has demonstrated important changes compared to the Raman spectra, suggesting strong structural modifications due to the cation displacements rather to those of the oxygenion. Our results reveal that polar distortions originating in local symmetry breaking, i.e. local non-centrosymmetry, resulting in Cr off-centring. (C) 2014 Elsevier B. V. Allrights reserved.

【 授权许可】

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