Analysis of moiré patterns in images of thin YBa2Cu3O7-δ films on MgO

1992 ◽  
Vol 50 (1) ◽  
pp. 236-237
Author(s):  
M. Grant Norton ◽  
C. Barry Carter
Keyword(s):  
Metal Films ◽  
Double Diffraction ◽  
Bright Field ◽  
Small Deviations ◽  
Moiré Fringes ◽  
Moire Patterns ◽  
Interfacial Strain ◽  
Fringe Patterns ◽  
Moiré Patterns ◽  
Scattered Beam

Moiré fringes arise from the interference between diffracted beams from two overlapping crystals (double diffraction) and in the bright-field case the forward scattered beam. The fringe patterns act as magnifiers of lattice imperfections and small deviations from perfect crystallographic orientation and symmetry. Moiré patterns have been used previously to study, for example, the growth of metal films on substrates such as molybdenum disulfide—which can easily be prepared to electron transparency. Moiré patterns can be used to identify microstructural defects in epitactic deposits. For example, the presence of rotationally misaligned grains, the presence of dislocations, and residual interfacial strain will be revealed in the fringe pattern.

Moire Fringes on Precipitates in Quenched and Aged Beryllium

1968 ◽  
Vol 26 ◽  
pp. 426-427
Author(s):  
F. J. Fraikor ◽  
A. W. Brewer
Keyword(s):  
Ternary Phase ◽  
Volume Fraction ◽  
Age Hardening ◽  
Orientation Relationships ◽  
Solute Content ◽  
Moiré Fringes ◽  
Moire Patterns ◽  
Total Volume Fraction ◽  
Diffraction Patterns ◽  
Moiré Patterns

A number of investigators have examined moire patterns on precipitate particles in various age-hardening alloys. For example, Phillips has analyzed moire fringes at cobalt precipitates in copper and Von Heimendahl has reported on moire fringes in the system Al-Au. Recently, we have observed moire patterns on impurity precipitates in beryllium quenched in brine from 1000°C and aged at various temperatures in the range of 500-800°C. This heat treatment of beryllium rolled from vacuum cast ingots produces the precipitation of both an fee ternary phase, AlFeBe4, and an hcp binary phase, FeBe11. However, unlike a typical age-hardening alloy, the solute content of this material is low (less than 1000 ppm of Fe and 600 ppm of Al) and hence the total volume fraction of precipitates is small. Therefore there is some difficulty in distinguishing the precipitates and their orientation relationships with the beryllium matrix since the weak precipitate spots generally do not appear on the diffraction patterns.

The Use of Moiré Patterns in TEM Images to Measure Precipitate Composition in Al-Si-Ge Alloys

2001 ◽  
Vol 7 (S2) ◽  
pp. 238-239
Author(s):  
V. Radmilovic ◽  
D. Mitlin ◽  
S. Hinderberger ◽  
U. Dahmen
Keyword(s):  
Elastic Interaction ◽  
Lattice Parameter ◽  
Multiphase System ◽  
Orientation Relationships ◽  
Precipitate Crystal ◽  
Large Matrix ◽  
Moiré Fringes ◽  
Moire Patterns ◽  
Lattice Images ◽  
Moiré Patterns

Moiré patterns are commonly formed in multiphase system when diffracting planes of similar spacing and orientation lead to interference effects. They can be used experimentally to evaluate the stress distribution in materials [1], to analyze orientation relationships and latttice strain in diffraction contrast microscopy, or, combined with the related geometrical phase technique, to analyze displacements in high resolution lattice images [2,3]. The interpretation of moiré fringes is often not straightforward due to the elastic interaction between the crystals at the interface and the dynamical nature of electron diffraction [4]. However, if the two lattices are fully relaxed, or if a small precipitate crystal is embedded in a large matrix, moiré patterns can give a simple and direct measure of orientation and lattice constants. in the present work, the moiré technique has been applied to the quantitative analysis of lath-shaped Ge or Ge-Si precipitates in Al with the aim to determine the composition (the Si:Ge ratio) from the lattice parameter indicated by the moiré fringes.

Moiré fringes of higher-order harmonics versus higher-order moiré patterns

2018 ◽  
Vol 57 (33) ◽  
pp. 9777 ◽  
Author(s):  
Mohammad Yeganeh ◽  
Saifollah Rasouli
Keyword(s):  
Higher Order ◽  
Moiré Fringes ◽  
Moire Patterns ◽  
Moiré Patterns

Measurement of Moiré Patterns in 3D Display

2019 ◽  
pp. 986
Author(s):  
Hea In Jeong ◽  
Seo Young Choi ◽  
Young Ju Jeong
Keyword(s):  
3D Display ◽  
Moire Patterns ◽  
Moiré Patterns

Main Crystallographic Situations for the Formation of X-Ray Moiré Patterns

1991 ◽  
Vol 126 (1) ◽  
pp. 41-47
Author(s):  
P. A. Bezirganyan ◽  
S. E. Bezirganyan ◽  
A. O. Aboyan
Keyword(s):  
X Ray ◽  
Moire Patterns ◽  
Moiré Patterns

scholarly journals Vortex dynamics, pinning, and angle-dependent motion on moiré patterns

2021 ◽  
Vol 104 (2) ◽  
Author(s):  
Wenzhao Li ◽  
C. J. O. Reichhardt ◽  
B. Jankó ◽  
C. Reichhardt
Keyword(s):  
Vortex Dynamics ◽  
Moire Patterns ◽  
Moiré Patterns

scholarly journals An equivalent configuration approach for the moiré patterns appearing due to the reflecting surface in display system

2014 ◽  
Vol 22 (20) ◽  
pp. 24840 ◽  
Author(s):  
Seok-Joo Byun ◽  
Seok Yong Byun ◽  
Jangkyo Lee ◽  
Won Mok Kim ◽  
Taek-Sung Lee
Keyword(s):  
Display System ◽  
Moire Patterns ◽  
Reflecting Surface ◽  
Moiré Patterns

scholarly journals Giant magnetic field from moiré induced Berry phase in homobilayer semiconductors

2019 ◽  
Vol 7 (1) ◽  
pp. 12-20 ◽  
Author(s):  
Hongyi Yu ◽  
Mingxing Chen ◽  
Wang Yao
Keyword(s):  
Magnetic Field ◽  
Berry Phase ◽  
Transition Metal Dichalcogenides ◽  
Real Space ◽  
Quantum Spin ◽  
Moire Patterns ◽  
Metal Dichalcogenides ◽  
Berry Phases ◽  
Different Origins ◽  
Moiré Patterns

Abstract When quasiparticles move in condensed matters, the texture of their internal quantum structure as a function of position and momentum can give rise to Berry phases that have profound effects on the material’s properties. Seminal examples include the anomalous Hall and spin Hall effects from the momentum-space Berry phases in homogeneous crystals. Here, we explore a conjugate form of the electron Berry phase arising from the moiré pattern: the texture of atomic configurations in real space. In homobilayer transition metal dichalcogenides, we show that the real-space Berry phase from moiré patterns manifests as a periodic magnetic field with magnitudes of up to hundreds of Tesla. This quantity distinguishes moiré patterns from different origins, which can have an identical potential landscape, but opposite quantized magnetic flux per supercell. For low-energy carriers, the homobilayer moirés realize topological flux lattices for the quantum-spin Hall effect. An interlayer bias can continuously tune the spatial profile of the moiré magnetic field, whereas the flux per supercell is a topological quantity that can only have a quantized jump observable at a moderate bias. We also reveal the important role of the non-Abelian Berry phase in shaping the energy landscape in small moiré patterns. Our work points to new possibilities to access ultra-high magnetic fields that can be tailored to the nanoscale by electrical and mechanical controls.

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