Strain Relief in Cu-Pd Heteroepitaxy

Lu, Yafeng; Przybylski, M.; Trushin, Oleg; Wang, W. H.; Barthel, J.; Granato, Enzo; Ying, S. C.; Ala-Nissilä, Tapio

doi:10.1103/physrevlett.94.146105

Cited by 15 publications

(33 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…17 The energy of a Cu impurity in a Pd host is close to the experimental value 16 and the surface energies are consistent with the measurements 16 and first-principles studies. 18 The potential correctly predicts the system to be in the wetting regime although for a bulk alloy it favors fcc instead of the observed B2 bcc phase.…”

supporting

confidence: 84%

Stress release mechanisms for Cu on Pd(111) in the submonolayer and monolayer regimes

et al. 2010

Self Cite

View full text Add to dashboard Cite

We study the strain relaxation mechanisms of Cu on Pd͑111͒ up to the monolayer regime using two different computational methodologies, basin-hopping global optimization and energy minimization with a repulsive bias potential. Our numerical results are consistent with experimentally observed layer-by-layer growth mode. However, we find that the structure of the Cu layer is not fully pseudomorphic even at low coverages. Instead, the Cu adsorbates forms fcc and hcp stacking domains, separated by partial misfit dislocations. We also estimate the minimum energy path and energy barriers for transitions from the ideal epitaxial state to the fcc-hcp domain pattern. Introduction. Metallic surfaces and nanostructures are essential systems for heterogeneous catalysis. Combination of two metals can lead to significant improvements in the variability and frequency of the reactions catalyzed. To prepare controlled nanostructures, it is crucial to understand the growth and stability of heteroepitaxial metal systems, in particular for close-packed surfaces. On fcc͑111͒ it has been found that to release the stress, the overlayer can adopt several alternative strategies which lead to a structure of domains separated by partial misfit dislocations.1-7 The domains correspond to the two favorable sites, fcc and hcp. This behavior is expected to be ubiquitous and should not depend strongly on the interaction potentials or the overlayer-substrate mismatch.

show abstract

supporting

confidence: 84%

Stress release mechanisms for Cu on Pd(111) in the submonolayer and monolayer regimes

et al. 2010

Self Cite

View full text Add to dashboard Cite

show abstract

“…Similar structures have been reported in other metallic thin film systems, starting at a critical thickness [30,31]. They do have in common with ours, a large tensile strain value (14% in the case of Fe on Au(1 0 0) and 7.8% for Cu on Pd(1 0 0)).…”

Section: Discussionsupporting

confidence: 79%

“…4c) a net-like appearance that dominates the complete landscape. Similar structures have also been observed in other fcc(1 0 0) heteroepitaxial systems [31].…”

Section: Discussionsupporting

confidence: 64%

Growth morphology of ultra-thin Ni films on Pd(100)

Parra

Häberle

2010

Surface Science

View full text Add to dashboard Cite

“…Moreover, the critical thickness h c above which the strained film grows incoherently by introducing misfit dislocations is found ≈3 times larger in bilayers than in single layers [65]. A more recent study on the pseudoepitaxial growth of high lattice-mismatched heterostructures has shown the pronounced tensile-compressive asymmetry [66], wherein the h c is found to be a few monolayers under compression, for instance, Huang et al [67] found h c ≈ 3 ML, and 9 ML under tensile strain. Building on the above arguments, we can conclude that the formation of a misfit dislocation network in the case of Dy/Sc SLs may be prevented by the combination of two factors, the multilayer structure effect and the large tensile-compressive asymmetry, so that for the Dy layers h c > t Dy ≈ 8 ML, in good accord with our experimental findings.…”

Section: A Superlattices Structural Characterization: Transmission Ementioning

confidence: 97%

In-plane uniaxial magnetic anisotropy induced by anisotropic strain relaxation in high lattice-mismatched Dy/Sc superlattices

2014

View full text Add to dashboard Cite

We report on the magnetic and structural characterization of high lattice-mismatched [Dy 2nm /Sc t Sc ] superlattices, with variable Sc thickness t Sc = 2-6 nm. We find that the characteristic in-plane effective hexagonal magnetic anisotropy K 6,ef 6 reverses sign and undergoes a dramatic reduction, attaining values of ≈13-24 kJm −3 , when compared to K 6 6 = −0.76 MJm −3 in bulk Dy. As a result, the basal plane magnetic anisotropy is dominated by a uniaxial magnetic anisotropy (UMA) unfound in bulk Dy, which amounts to ≈175-142 kJm −3 . We attribute the large downsizing in K 6,ef 6 to the compression epitaxial strain, which generates a competing sixfold magnetoelastic (MEL) contribution to the magnetocrystalline (strain-free) magnetic anisotropy. Our study proves that the in-plane UMA is caused by the coupling between a giant symmetry-breaking MEL constant M 2 γ,2 ≈ 1 GPa and a morphic orthorhombiclike strain ε γ,1 ≈ 10 −4 , whose origin resides on the arising of an in-plane anisotropic strain relaxation process of the pseudoepitaxial registry between the nonmagnetic bottom layers in the superstructure. This investigation shows a broader perspective on the crucial role played by epitaxial strains at engineering the magnetic anisotropy in multilayers.

show abstract

Strain Relief in Cu-Pd Heteroepitaxy

Cited by 15 publications

References 19 publications

Stress release mechanisms for Cu on Pd(111) in the submonolayer and monolayer regimes

Stress release mechanisms for Cu on Pd(111) in the submonolayer and monolayer regimes

Growth morphology of ultra-thin Ni films on Pd(100)

In-plane uniaxial magnetic anisotropy induced by anisotropic strain relaxation in high lattice-mismatched Dy/Sc superlattices

Contact Info

Product

Resources

About