Hyperfine interaction and electronic spin fluctuation study on Sr${}_{2-x}$La${}_x$FeCoO${}_6$ (x = 0, 1, 2) by high-resolution back-scattering neutron spectroscopy

Abstract

The study of hyperfine interaction by high-resolution inelastic neutron scattering is not very well known compared to the other competing techniques viz. NMR, Mössbauer, PACS etc. Also the study is limited mostly to magnetically ordered systems. Here we report such study on Sr${}_{2-x}$La${}_x$FeCoO${}_6$ (x = 0, 1, 2) of which first (Sr${}_2$FeCoO${}_6$ with x = 0) has a canonical spin spin glass, the second (SrLaFeCoO${}_6$ with x = 1) has a so-called magnetic glass and the third (La${}_2$FeCoO${}_6$ with x = 2) has a magnetically ordered ground state. Our present study revealed clear inelastic signal for SrLaFeCoO${}_6$, possibly also inelastic signal for Sr${}_2$FeCoO${}_6$ below the spin freezing temperatures $T_{sf}$ but no inelastic signal at all for for the magnetically ordered La${}_2$FeCoO${}_6$ in the neutron scattering spectra. The broadened inelastic signals observed suggest hyperfine field distribution in the two disordered magnetic glassy systems and no signal for the third compound suggests no or very small hyperfine field at the Co nucleus due to Co electronic moment. For the two magnetic glassy system apart from the hyperfine signal due only to Co, we also observed electronic spin fluctuations probably from both Fe and Co electronic moments. \end{abstract}

References in corpus (6)

• SPHERES, Jülich's High-Flux Neutron Backscattering Spectrometer at FRM II
• Triplet and in-gap magnetic states in the ground state of the quantum frustrated FCC antiferromagnet Ba2YMoO6
• Observation of spin glass state in weakly ferromagnetic Sr${}_2$FeCoO${}_6$ double perovskite
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• Direct evidence for the magnetic ordering of Nd ions in NdMn${}_2$Si${}_2$ and NdMn${}_2$Ge${}_2$ by high resolution inelastic neutron scattering
• Direct observation of low energy nuclear spin excitations in HoCrO${}_3$ by high resolution neutron spectroscopy

Cited by in corpus (2)

• Successive spin reorientation and rare earth ordering in Nd${}_{0.5}$Dy${}_{0.5}$FeO${}_3$: Experimental and $Ab$-$initio$ investigations
• Contrasting the magnetism in La${}_{2-x}$Sr${}_x$FeCoO${}_6$ ($x$ = 0, 1, 2) double perovskites: the role of electronic and cationic disorder