55MnNMR investigation ofNd1−x

Abstract

55 Mn nuclear magnetic resonance ͑NMR͒ in Nd 1Ϫx Sr x MnO 3 (0.1рxр0.5) manganites provides local evidence of the magnetic inhomogeneities arising from the electronic structure changes below T C . The temperature dependences of magnetization, resistivity, and NMR spectra were compared in samples in the ferromagnetic insulating, ferromagnetic metallic, and charge-ordered phases. Spin-spin relaxation enhancement around 15 K is attributed to a critical slowing down of the Nd sublattice.

Neutron diffraction, magnetization, and ESR studies of pseudocubicNd0.75Ba0.25MnO3and its critical behavior aboveTCRyzhov1, Lazuta2, Smirnov3 et al. 2005Phys. Rev. B190130View full textAdd to dashboardCite

“…The ground state of Nd 3+ ion (total moment J = 9/2, L = 6 and S = 3/2) is split by a low symmetric (lower than cubic) crystal field into the five doublets described by the effective spins S = 1/2. It is expected that a Mn-Nd exchange interactionĴ 12 is larger than that of the Nd-Nd [9,23]. We will show that the weak anisotropic couplingĴ 12 can give the needed contribution in Γ(τ ).…”

“…In Nd 0.7 Ba 0.3 MnO 3 , the ordering of the Nd moments, that develops below 20 K [7], changed the magnetic and transport properties [8]. As study of the Nd 1−x Sr x MnO 3 (0.1 ≤ x ≤ 0.5) showed, the Nd magnetic subsystem came also into play at the low temperatures due to its ordering [9]. At the same time, no effects of the Mn-Nd coupling were found near T C in the investigations of critical static behavior of Nd 0.6 Pb 0.4 MnO 3 [10] and critical dynamics of Nd 1−x Sr x MnO 3 (x ≈ 0.5) [11].…”

Three-dimensional Ising critical behavior inR0.6Sr0.4MnO3(R

“…A first possibility is the rare-earth magnetism of Pr and Nd, which might interact with the manganese spin network, as it has been proposed in some manganites [21,34]. Besides, it must be taken into account that although these concentrations (x = 0.4) are thought to be far from the charge-ordered antiferromagnetic phase with charge localization (x = 0.5) where phase segregation is well established [35], in some studies it was found that Nd 1−x Sr x MnO 3 (x = 0.3,0.4) also presented a weaker mechanism of carrier localization as well as phase segregation [36][37][38]. In other papers for x = 0.3, a competition between the double exchange mechanism and correlations arising from coupled spin and lattices degrees of freedom was found [24,37].…”

Praseodymium-deficiency effects upon physical properties of bulk manganite

“…The shape of spectrum in the field of 1 T clearly differs from that taken in zero field, which suggests that applying the field removes the pinning of domain walls. The multi-peak spectra have also been observed for ferromagnetic metallic Nd 1Àx Sr x MnO 3 compounds [7].…”