Magnetocrystalline and magnetoelastic basal plane anisotropies in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mrow><mml:mi mathvariant="normal">Ho</mml:mi></mml:mrow><mml:mo>∕</mml:mo><mml:mrow><mml:mi mathvariant="normal">Lu</mml:mi></mml:mrow></mml:mrow></mml:math>superlattices

Benito, L.; Arnaudas, J.I.; Ciria, M.; Fuente, C. de la; Moral, A. del; Ward, R. C. C.; Wells, M. R.

doi:10.1103/physrevb.70.052403

Cited by 16 publications

(27 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This affects the exchange interaction and, hence, the type of magnetic order and transition temperatures in ML structures [16][17][18]. Additionally, combined with hybridization effects, symmetry breaking and epitaxial strain influence the magnetic anisotropy and magnetoelastic interactions [19], giving rise to a different magnetic behavior compared to that of thick films.…”

Section: Introductionmentioning

confidence: 99%

Structure and magnetism of Tm atoms and monolayers on W(110)

et al. 2014

View full text Add to dashboard Cite

We investigated the growth and magnetic properties of Tm atoms and monolayers deposited on a W(110) surface using scanning tunneling microscopy and x-ray magnetic circular and linear dichroism. The equilibrium structure of Tm monolayer films is found to be a strongly distorted hexagonal lattice with a Moiré pattern due to the overlap with the rectangular W(110) substrate. Monolayer as well as isolated Tm adatoms on W present a trivalent ground-state electronic configuration, contrary to divalent gas phase Tm and weakly coordinated atoms in quench-condensed Tm films. Ligand field multiplet simulations of the x-ray absorption spectra further show that Tm has a |J = 6,J z = ±5 electronic ground state separated by a few meV from the next lowest substates |J = 6,J z = ±4 and |J = 6,J z = ±6 . Accordingly, both the Tm atoms and monolayer films exhibit large spin and orbital moments with out-of-plane uniaxial magnetic anisotropy. X-ray magnetic dichroism measurements as a function of temperature show that the Tm monolayers develop antiferromagnetic correlations at about 50 K. The triangular structure of the Tm lattice suggests the presence of significant magnetic frustration in this system, which may lead to either a noncollinear staggered spin structure or intrinsic disorder.

show abstract

Section: Introductionmentioning

confidence: 99%

Structure and magnetism of Tm atoms and monolayers on W(110)

et al. 2014

View full text Add to dashboard Cite

show abstract

“…At a glance, the MEL constants associated to the tetragonal MS mode ε α2 are around about an order of magnitude larger than those associated to the volume expansion ε α1 . The quick analysis of the α-MEL constants reveals the following key features: (1) The tetragonal MS mode is considerably more efficient than the volume expansion mode in decreasing the sixfold magnetic anisotropic energy, since it turns out that M 10, being fully coherent with a prior study of the impact that an in-plane compression epitaxial strain has upon the sixfold magnetic anisotropy [47]. (2) The uniaxial magnetic anisotropy increases rapidly under the appearance of ε α2 ; notice that M 2 α2 = 0.9 GPa and the ratio M 7.9.…”

Section: Thermal Analysis Of the Volume And Tetragonal Magnetostrmentioning

confidence: 77%

“…(11), replicates a change of sign in K 6,eff 6 as H is swept in the [Ho 85 /Lu 15 ] 50 superlattice (SL), in which the SFT was first observed [21], the first aspect we must consider is the influence that the finite size [50] of the Ho layers has upon the MEL constants. Thus, as an earlier study [47] has shown, the development of typical epitaxial strains in multilayered rare earth based systems originated a negligible alteration, if any at all, in the γ -MEL constants, however, the α-MEL ones experienced an appreciable strain-induced modification, which is in a general case modelled as follows [23]:…”

Section: Spin-flop Transition Model In Holmium: Competing Mel Anmentioning

confidence: 99%

“…Besides, we will assume that the developed epitaxial strain in the target Ho/Lu SL is mostly isotropic in the deposition plane, as a prior study suggested [47]. In this way, making the following identification ε xx = ε xx ≡ ε and ε zz ≡ ε ⊥ , where ε and ε ⊥ are the in-and out-ofplane strains, respectively, and modeling the thickness dependence of ε by the relationship ε = ε 0 t Lu /(ct Lu + t Ho ) [51], where ε 0 = a Lu −a Ho a Ho = −0.0204, is the lattice mismatch, a Ho(Lu) is the in-plane lattice parameter [16] for Ho(Lu), t Ho,Lu is the Ho(Lu) nominal layer thickness [85 monolayers (MLs) for Ho and 15 MLs for the Lu layers] and c = 0.95 is a constant resulting from the ratio between Ho and Lu elastic constants and, finally, making use of the Poisson's ratio ε ⊥ = −2ε c 13 /c 33 [52], where the ratio c 13 /c 33 = 0.26 [46] in bulk Ho, it is straightforward to calculate that ε α1 3 2 ε and ε α2 − 1 4 ε , where ε = −0.003 08.…”

Section: Spin-flop Transition Model In Holmium: Competing Mel Anmentioning

confidence: 99%

See 1 more Smart Citation

Spin-flop transition driven by competing magnetoelastic anisotropy terms in a spin-spiral antiferromagnet

Benito

2015

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

Holmium, the archetypical system for spin-spiral antiferromagnetism, undergoes an in-plane spin-flop transition earlier attributed to competing symmetry-breaking and fully symmetric magnetoelastic anisotropy terms [Phys. Rev. Lett. 94, 227204 (2005)], which underlines the emergence of sixfold magnetoelastic constants in heavy rare earth metals, as otherwise later studies suggested. A model that encompasses magnetoelastic contributions to the in-plane sixfold magnetic anisotropy is laid out to elucidate the mechanism behind the spin-flop transition. The model, which is tested in a Ho-based superlattice, shows that the interplay between competing fully symmetric α-magnetoelastic and symmetry-breaking γ -magnetoelastic anisotropy terms triggers the spin reorientation. This also unveils the dominant role played by the sixfold exchange magnetostriction constant, where D 66 α2 0.32 GPa against its crystal-field counterpart M 66 α2 −0.2 GPa, in contrast to the crystal-field origin of the symmetry-breaking magnetostriction in rare earth metals.

show abstract

“…Here we report on the distinctive way in which finite-size and the spin's dimensionality effects determine the MAE in ultrathin layers. Taking RE superlattices (SLs) as a model system [33], which is featured by the precise modeling of their MAE [29,30], we demonstrate that the two dimensionality of the spin system in ultrathin RE layers imprints a universal, rank-independent temperature scaling on the MAE constant as a quadratic power law of the reduced magnetization, in agreement with early predictions [34].We have investigated two ultrathin strain-alike RE-based SLs, mainly, [Dy 8±1 /Sc 8±1 ] 50 and [Ho 8±1 /Lu 18±2 ] 75 , hereafter referred to as Dy/Sc and Ho/Lu SLs, where the subindexes indicate the number of monolayers (MLs) in each layer, and 50 and 75 refer to the number of repetitions of the Dy/Sc and Ho/Lu bilayers, respectively. Both SLs were grown by a molecular beam epitaxy technique in a Balzers UMS630 facility, with a base pressure of better than 2 × 10 −10 mbar and deposited onto epi-polished (1120)-oriented Al 2 O 3 substrates, following well-established growth techniques [35,36].…”

mentioning

confidence: 99%

Universal scaling of the magnetic anisotropy in two-dimensional rare-earth layers

Benito

Ward

2015

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

Unraveling the influence that low dimensionality has upon the spin's stability in two-dimensional (2D) systems is instrumental for the efficient engineering of energy barriers in ultrathin magnetic layers. Taking rare-earth-based ultrathin multilayered nanostructures as a model system, we have investigated the dissimilar impact that low dimensionality and finite-size effects have upon the magnetic anisotropy energy (MAE) at the nanoscale. We conclusively show that the reduced dimensionality of the spin's system in 2D ferromagnetic layers imprints on the MAE constants a universal temperature decay as a quadratic power law of the reduced magnetization. This result is in agreement with predictions, although in marked contrast to the rank-dependent, thereby faster, decay of the MAE constants observed in three-dimensional nanostructures. [7], and plays an essential part in spin dynamics [8], has gathered huge interest [9,10], being in the spotlight of countless studies aiming to explore and gain control over the MAE of nanometersized matter [11].The relentless trend for miniaturization imposes the shrinking of the device size down to the nanoscale, which entails the arising of dominating surface/interface [12] contributions into MAE. In this way, the symmetry breaking of the lattice potential at the nanosystem boundaries gives rise to huge energy barriers [13,14], which are predominantly contributed by perimeter-edge ions [15]. On the contrary, as layer thickness becomes comparable to the spin-spin exchange range, the magnetic ordering temperatures [16][17][18] are shifted towards lower ones and the spin polarization [19] diminishes faster than in bulk systems as temperature increases. These two facts reflect in the enhancing efficacy of thermally activated spin waves [20] to annihilate long-range magnetic order [21] at the nanoscale.Newly engineered magnetic two-dimensional (2D) hybrid systems [22] have opened up an exciting new route for faster, more power-efficient spintronics [23], albeit they are not exempt from fundamental challenges. Thus, the reduced dimensionality of the crystal field in transition-metal-based nanosystems is well known to revive orbital moments, which contributes to stabilize the magnetic order in nanometer-sized matter [13,24]. However, the impact that the spin's low dimensionality has upon their thermal stability and, therefore, its crucial role in determining their magnetic response, is still poorly understood. The thermal stability of 2D magnets could be elucidated by measuring the temperature scaling of the model-independent MAE in ultrathin layers; nevertheless, such an experimental test has remained elusive upon until now. Here we report on the distinctive way in which finite-size and the spin's dimensionality effects determine the MAE in ultrathin layers. Taking RE superlattices (SLs) as a model system [33], which is featured by the precise modeling of their MAE [29,30], we demonstrate that the two dimensionality of the spin system in ultrathin RE layers imprints a universal, rank-i...

show abstract

Magnetocrystalline and magnetoelastic basal plane anisotropies inHo∕Lusuperlattices

Cited by 16 publications

References 21 publications

Structure and magnetism of Tm atoms and monolayers on W(110)

Structure and magnetism of Tm atoms and monolayers on W(110)

Spin-flop transition driven by competing magnetoelastic anisotropy terms in a spin-spiral antiferromagnet

Universal scaling of the magnetic anisotropy in two-dimensional rare-earth layers

Contact Info

Product

Resources

About