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Prokscha, T.; Birke, M.; Forgan, E. M.; Glückler, H.; Höfer, A.; Jackson, Trevor; Küpfer, K.; Litterst, F. J.; Morenzoni, E.; Niedermayer, Ch.; Pleines, M; Riseman, T. M.; Schatz, Axel; Schätz, G.; Weber, H.P.; Binns, C.

doi:10.1023/a:1017094700593

Cited by 9 publications

(6 citation statements)

References 9 publications

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“…The temperature range for LEM-μ + SR measurements was between 10 and 320 K for a cryostat and 300 and 500 K for an oven. The details of LEM-μ + are described elsewhere [25][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

Li-ion diffusion inLi4Ti5O12andLiTi2O4

et al. 2015

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Lithium diffusion in spinel Li 4 Ti 5 O 12 and LiTi 2 O 4 compounds for future battery applications has been studied with muon spin relaxation (μ + SR). Measurements were performed on both thin-film and powder samples in the temperature range between 25 and 500 K. For Li 4 Ti 5 O 12 and above about ∼200 K, the field distribution width () is found to decrease gradually, while the field fluctuation rate (ν) increases exponentially with temperature. For LiTi 2 O 4 , on the contrary, the (T) curve shows a steplike decrease at ∼350 K, around which the ν(T) curve exhibits a local maximum. These behaviors suggest that Li + starts to diffuse above around 200 K for both spinels. Assuming a jump diffusion of Li + at the tetrahedral 8a site to the vacant octahedral 16c site, diffusion coefficients of Li + at 300 K in the film samples are estimated as (3.2 ± 0.8) × 10 −11 cm 2 /s for Li 4 Ti 5 O 12 and (3.6 ± 1.1) × 10 −11 cm 2 /s for LiTi 2 O 4. Further, some small differences are found in both thermal activation energies and Li-ion diffusion coefficients between the powder and thin-film samples.

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“…The temperature range for LEM-μ + SR measurements was between 10 and 320 K for a cryostat and 300 and 500 K for an oven. The details of LEM-μ + are described elsewhere [25][26][27][28].…”

Section: Introductionmentioning

confidence: 99%

Li-ion diffusion inLi4Ti5O12andLiTi2O4

et al. 2015

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“…% Co in Cu, 33,34 and a dilute dispersion of 0.1 vol % Fe in an Ag thin film. [35][36][37] There are some especially advantageous features of SR for the Fe-Cu-Ag system, notably that the data obtained are selectively sensitive to the relaxing moments in the sample, and that the measurement time scales fall in a region of interest close to those afforded by Mössbauer spectroscopy and by ac susceptibility.…”

Section: Introductionmentioning

confidence: 99%

Magnetic relaxation in the nanoscale granular alloyFe20Cu20Ag6

et al. 2001

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The structural and magnetic properties of a representative member of a class of technologically relevant ternary metallic alloys have been studied in detail. The alloy, of composition Fe 20 Cu 20 Ag 60 , is a member of the family of nanoscale granular alloys that are of current interest in both giant magnetoresistive alloys and nanocrystalline soft magnets. Samples were produced by mechanical alloying ͑70 h, argon sealed͒ and were homogeneous according to scanning electron microscopy and electron microprobe analysis. Room-temperature magnetoresistance measurements in applied fields up to Hϭ90 kOe gave a value of 5% ͑at 90 kOe͒ for the ͓R(H)ϪR(0)͔/R(0) ratio. Rietveld calculations on high-resolution image plate data using a synchrotron source (ϭ0.6920 Å) showed that the specimen comprised a dispersion of bcc Fe 60 Cu 40 ͑Im-3m, a ϭ2.951 Å͒ particles of mean size 5.5 nm in an fcc Ag 90 Cu 10 ͑Fm-3m, aϭ4.057 Å͒ matrix. This structure was stable up to 380 K as revealed by differential scanning calorimetry. dc magnetization ͑peaks in zero-fieldcooled data͒ and frequency-dependent ac susceptibility ͑in external dc magnetic fields from zero to 500 Oe͒ measurements showed blocking transitions between 280 and 300 K, with the onset of superparamagnetic behavior at higher temperatures. The superparamagnetic regime was confirmed at room temperature by the observation of anhysteretic M (H) curves, and through zero field and applied field Mössbauer experiments in which a combined singlet plus doublet spectrum was transformed to a magnetically split sextet on application of an 11-kOe field. In all cases the blocking transitions were clearly affected by the existence of intergranular interactions, which shifted them to higher temperatures than would be expected from noninteracting grains. Evidence of intergranular interactions were also found in the dynamic behavior of the ac susceptibility data ͑small frequency-dependent shifts in the blocking temperature, Vogel-Fulcher activation processes͒. Muon spectroscopy was found to provide excellent corroborating information on the blocking transition, with a clear peak being found in the exponential decay rates of the depolarization spectra. The result establishes the feasibility of using muon spin relaxation to probe other superparamagnetic materials, with the advantage that measurements can be conducted in absolutely zero field.

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“…The temperature range for LEM-µ + SR measurements was between 10 and 320 K for a cryostat and 300 and 500 K for an oven. The details of LEM-µ + SR are described elsewhere [10][11][12][13]. Figure 2 shows the temperature variation of the zero field (ZF) µ + SR spectrum for Li[Ni 1/2 Mn 3/2 ]O 4 measured at 150, 300, and 500 K. The ZF-spectrum exhibits a static behavior at 150 K, while it becomes dynamic with increasing temperature.…”

Section: Methodsmentioning

confidence: 99%

Li-Diffusion in Spinel Li[Ni_1/2Mn_3/2]O₄Powder and Film Studied with μ⁺SR

Sugiyama

Nozaki

Umegaki

et al. 2018

Proceedings of the 14th International Conference on Muon Spin Rotation, Relaxation and Resonance (ΜSR2017)

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A dynamic behavior in spinel Li[Ni 1/2 Mn 3/2 ]O 4 has been studied with µ + SR measurements in film and powder samples in the temperature range between 5 and 500 K. Both samples exhibited a broad ferromagnetic transition below 120 K, indicating the random distribution of Ni and Mn ions at the octahedral 16d site. Above 150 K, the ZF-µ + SR spectrum showed a dynamic behavior well explained by a dynamic Kubo-Toyabe function. Assuming a jump diffusion of Li + at the tetrahedral 8a site to the vacant octahedral 16c site, a diffusion coefficient of Li + is estimated as ∼ 5×10 −11 cm 2 /s at 300 K and ∼ 8 × 10 −11 cm 2 /s at 350 K and ∼ 14 × 10 −11 cm 2 /s at 400 K, with thermal activation energy E a ∼ 0.1 eV.

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Cited by 9 publications

References 9 publications

Li-ion diffusion inLi4Ti5O12andLiTi2O4

Li-ion diffusion inLi4Ti5O12andLiTi2O4

Magnetic relaxation in the nanoscale granular alloyFe20Cu20Ag6

Li-Diffusion in Spinel Li[Ni_1/2Mn_3/2]O₄Powder and Film Studied with μ⁺SR

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Untitled

Cited by 9 publications

References 9 publications

Li-ion diffusion inLi4Ti5O12andLiTi2O4

Li-ion diffusion inLi4Ti5O12andLiTi2O4

Magnetic relaxation in the nanoscale granular alloyFe20Cu20Ag6

Li-Diffusion in Spinel Li[Ni1/2Mn3/2]O4Powder and Film Studied with μ+SR

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Li-Diffusion in Spinel Li[Ni_1/2Mn_3/2]O₄Powder and Film Studied with μ⁺SR