Direct observation of double exchange in ferromagnetic La0.7Sr0.3CoO3 by broadband ellipsometry

Article

关键词: OPTICAL CONDUCTIVITY;    ELECTRONIC-STRUCTURE;    TRANSITION;    TEMPERATURE;    MANGANITES;   

DOI  :  10.1103/PhysRevB.97.045137

来源: SCIE

【 摘 要 】

We present results of our broadband ellipsometry measurements of the optical response of ferromagnetic La0.7Sr0.3CoO3. Our data show that the ferromagnetic transition is accompanied by a transfer of optical spectral weight from an absorption band centered at 1.5 eV to a narrow component of the Drude-like peak. The associated reduction of the intraband kinetic energy is significantly larger than k(B)T(c), confirming that the double exchange plays a major role in the ferromagnetism of doped cobaltites. In conjunction with results of recent theoretical studies, the temperature dependence of the Drude-like peak suggests that the double exchange is mediated by t(2g) orbitals.

【 授权许可】

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