Spin-Electron-Phonon Excitation in Re-based Half-Metallic Double Perovskites

Garcia-Flores, AF and Moreira, AFL and Kaneko, UF and Ardito, FM and Terashita, H and Orlando, MTD and Gopalakrishnan, J and Ramesha, K and Granado, E (2012) Spin-Electron-Phonon Excitation in Re-based Half-Metallic Double Perovskites. In: Physical Review Letters, 108 (17).

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Abstract

A remarkable hardening (similar to 30 cm(-1)) of the normal mode of vibration associated with the symmetric stretching of the oxygen octahedra for the Ba2FeReO6 and Sr2CrReO6 double perovskites is observed below the corresponding magnetic ordering temperatures. The very large magnitude of this effect and its absence for the antisymmetric stretching mode provide evidence against a conventional spin-phonon coupling mechanism. Our observations are consistent with a collective excitation formed by the combination of the vibrational mode with oscillations of Fe or Cr 3d and Re 5d occupations and spin magnitudes.

Item Type:	Journal Article
Publication:	Physical Review Letters
Publisher:	The American Physical Society
Additional Information:	Copyright of this article is belongs to The American Physical Society.
Keywords:	MAGNETORESISTANCE;TEMPERATURE;SR2CRREO6;CA;BA
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	22 Aug 2012 04:48
Last Modified:	22 Aug 2012 04:48
URI:	http://eprints.iisc.ac.in/id/eprint/44449

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