Magnetic Properties of Layered Transition Metal Compounds

Jongh, L.J. de

doi:10.1007/978-94-009-1860-3

Cited by 202 publications

(13 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such an angular dependence is typical for two-dimensional systems and is caused by the increasing dominance of long-wavelength fluctuations (or, in reciprocal space, q ∼ 0 modes) in lowdimensional magnets, as discussed in Refs. [46][47][48]. As at 70 K no additional contributions to ∆H(α) apart from the one related to the low dimensionality was observed, we conclude that the shift of the resonance line above T c is not caused by inhomogeneities in the sample, for which we also did not find any signature in the structural characterizations of the crystals, see Appendix A.…”

Section: B Esr and Fmrmentioning

confidence: 46%

“…This kind of angular dependence is typical for spin systems in an uncorrelated, i.e. paramagnetic, phase in which no significant interactions between the spins exist in any direction and, as a consequence, the reduced dimensionality does not affect the spin dynamics reflected in ∆H(α) [46,47]. Upon lowering the temperature, spin correlations start to grow, leading to a gradual change of the angular dependence.…”

Section: B Esr and Fmrmentioning

confidence: 92%

See 1 more Smart Citation

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr2Ge2Te6

et al. 2019

View full text Add to dashboard Cite

We report a comprehensive experimental investigation on the magnetic anisotropy in bulk single crystals of Cr2Ge2Te6, a quasi-two-dimensional ferromagnet belonging to the family of magnetic layered transition metal trichalcogenides that have attracted recently a big deal of interest with regard to the fundamental and applied aspects of two-dimensional magnetism. For this purpose electron spin resonance (ESR) and ferromagnetic resonance (FMR) measurements have been carried out over a wide frequency and temperature range. A gradual change in the angular dependence of the ESR linewidth at temperatures above the ferromagnetic transition temperature Tc reveals the development of two-dimensional spin correlations in the vicinity of Tc thereby proving the intrinsically low-dimensional character of spin dynamics in Cr2Ge2Te6. Angular and frequency dependent measurements in the ferromagnetic phase clearly show an easy-axis type anisotropy of this compound. Furthermore, these experiments are compared with simulations based on a phenomenological approach, which takes into account results of static magnetization measurements as well as high temperature g factors obtained from ESR spectroscopy in the paramagnetic phase. As a result the determined magnetocrystalline anisotropy energy density (MAE) KU is (0.48 ± 0.02) × 10 6 erg/cm 3 . This analysis is complemented by density functional calculations which yield the experimental MAE value for a particular value of the electronic correlation strength U . The analysis of the electronic structure reveals that the low-lying conduction band carries almost completely spin-polarized, quasihomogeneous, two-dimensional states. arXiv:1810.02560v3 [cond-mat.str-el]

show abstract

Section: B Esr and Fmrmentioning

confidence: 46%

Section: B Esr and Fmrmentioning

confidence: 92%

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr2Ge2Te6

et al. 2019

View full text Add to dashboard Cite

show abstract

“…This required a constant sample handling under Ar flow. As explained in the literature,43 the onset of magnetic order occurs at the inflection point between the minimum and the maximum, here at ∼15 K. The dotted vertical line shows the T N value as obtained from NMR data. Further details about the uncertainty in identifying T N are given in the discussion section.…”

mentioning

confidence: 60%

Chemical and hydrostatic-pressure effects on the Kitaev honeycomb material Na2IrO3

et al. 2018

View full text Add to dashboard Cite

The low-temperature magnetic properties of polycrystalline Na 2 IrO 3 , a candidate material for the realization of a quantum spin-liquid state, were investigated by means of muon-spin relaxation and nuclear magnetic resonance methods under chemical and hydrostatic pressure. The Li-for-Na chemical substitution promotes an inhomogeneous magnetic order, whereas hydrostatic pressure (up to 3.9 GPa) results in an enhancement of the ordering temperature T N . In the first case, the inhomogeneous magnetic order suggests either short-or long-range correlations of broadly distributed j = ½ Ir 4+ magnetic moments, reflecting local disorder. The increase of T N under applied pressure points at an increased strength of three dimensional interactions arising from interlayer compression.

show abstract

“…Above 40 K the angular dependence of the linewidth shows a (cos 2 (α) + 1) behavior which is regularly encountered in weakly correlated or three-dimensional exchange- narrowed spin systems (see, e.g., Refs. [28,29] and references therein). Below ∼35 K the angular dependence of the linewidth changes gradually and an additional contribution of the type (3 cos 2 (α) − 1) 2 becomes visible which results in a minimum at α ≈ 60 • and in a local maximum of ∆H at α = 90 • .…”

Section: Angular Dependencementioning

confidence: 99%

Coherent spin dynamics of solitons in the organic spin chain compounds(o-DMTTF)2X(X=Cl,Br)

et al. 2019

View full text Add to dashboard Cite

We studied the magnetic properties, in particular dynamics, of the correlated spins associated with natural defects in the organic spin chain compounds (o -DMTTF)2X (X = Br, Cl) by means of electron spin resonance (ESR) spectroscopy. Both materials exhibit spin-Peierls transitions at temperatures around 50 K [Foury-Leylekian et al., Phys. Rev. B 84, 195134 (2011)], which allow a separation of the properties of defects inside the chains from the magnetic response of the spin chains. Indeed, continuous wave ESR measurements performed over a wide temperature range evidence the evolution of the spin dynamics from being governed by the spins in the chains at elevated temperatures to a low-temperature regime which is dominated by defects within the spindimerized chains. In addition, contributions of triplon excitations to the ESR response below the transition temperature were observed which provides a spectroscopic estimate for the spin-gap of the studied systems. Moreover, details of spin dynamics deep in the spin-Peierls phase were investigated by pulse ESR experiments which revealed Rabi-oscillations as signatures of coherent spin dynamics. We discuss the results obtained from these complementary methods of ESR spectroscopy in terms of solitons localized at the defect sites within the chains. From a comparison of the characteristic damping times of the Rabi oscillations with measurements of the spin relaxation times by means of primary-echo decay and CPMG methods it becomes evident that inhomogeneities in local magnetic fields strongly contribute to the soliton decoherence.

show abstract

Magnetic Properties of Layered Transition Metal Compounds

Cited by 202 publications

References 69 publications

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr2Ge2Te6

Magnetic anisotropy and spin-polarized two-dimensional electron gas in the van der Waals ferromagnet Cr2Ge2Te6

Chemical and hydrostatic-pressure effects on the Kitaev honeycomb material Na2IrO3

Coherent spin dynamics of solitons in the organic spin chain compounds(o-DMTTF)2X(X=Cl,Br)

Contact Info

Product

Resources

About