57 research outputs found
Analytic reproducibility in articles receiving open data badges at the journal <i>Psychological Science</i>: an observational study
Moir\'e patterns on STM images of graphite from surface and subsurface rotated layer
We have observed with STM moir\'e patterns corresponding to the rotation of
one graphene layer on HOPG surface. The moir\'e patterns were characterized by
rotation angle and extension in the plane. Additionally, by identifying border
domains and defects we can discriminate between moir\'e patterns due to
rotation on the surface or subsurface layer. For a better understanding of
moir\'e patterns formation we have studied by first principles an array of
three graphene layers where the top or the middle layer appears rotated around
the stacking axis. We compare the experimental and theoretical results and we
show the strong influence of rotations both in surface and subsurface layers
for moir\'e patterns formation in corresponding STM images.Comment: 5 pages, 6 figure
Substrate-induced band gap opening in epitaxial graphene
Graphene has shown great application potentials as the host material for next
generation electronic devices. However, despite its intriguing properties, one
of the biggest hurdles for graphene to be useful as an electronic material is
its lacking of an energy gap in the electronic spectra. This, for example,
prevents the use of graphene in making transistors. Although several proposals
have been made to open a gap in graphene's electronic spectra, they all require
complex engineering of the graphene layer. Here we show that when graphene is
epitaxially grown on the SiC substrate, a gap of ~ 0.26 is produced. This gap
decreases as the sample thickness increases and eventually approaches zero when
the number of layers exceeds four. We propose that the origin of this gap is
the breaking of sublattice symmetry owing to the graphene-substrate
interaction. We believe our results highlight a promising direction for band
gap engineering of graphene.Comment: 10 pages, 4 figures; updated reference
Electronic Transport through YBCO Grain Boundary Interfaces between 4.2 K and 300 K
The current-induced dissipation in YBCO grain boundary tunnel junctions has
been measured between 4.2 K and 300 K. It is found that the resistance of 45
degree (100)/(110) junctions decreases linearly by a factor of four when their
temperature is increased from 100 K to 300 K. At the superconducting transition
temperature Tc the grain boundary resistance of the normal state and of the
superconducting state extrapolate to the same value.Comment: 14 pages, 4 figure
Unique determination of “subatomic” contrast by imaging covalent backbonding
The origin of so-called “subatomic” resolution in dynamic force microscopy has remained controversial since its first observation in 2000. A number of detailed experimental and theoretical studies have identified different possible physicochemical mechanisms potentially giving rise to subatomic contrast. In this study, for the first time we are able to assign the origin of a specific instance of subatomic contrast as being due to the back bonding of a surface atom in the tip−sample junction
Advances in atomic force microscopy
This article reviews the progress of atomic force microscopy (AFM) in
ultra-high vacuum, starting with its invention and covering most of the recent
developments. Today, dynamic force microscopy allows to image surfaces of
conductors \emph{and} insulators in vacuum with atomic resolution. The mostly
used technique for atomic resolution AFM in vacuum is frequency modulation AFM
(FM-AFM). This technique, as well as other dynamic AFM methods, are explained
in detail in this article. In the last few years many groups have expanded the
empirical knowledge and deepened the theoretical understanding of FM-AFM.
Consequently, the spatial resolution and ease of use have been increased
dramatically. Vacuum AFM opens up new classes of experiments, ranging from
imaging of insulators with true atomic resolution to the measurement of forces
between individual atoms.Comment: In press (Reviews of Modern Physics, scheduled for July 2003), 86
pages, 44 figure
Children Change Their Answers in Response to Neutral Follow‐Up Questions by a Knowledgeable Asker
Data & Analysis
All primary data files for this project are available in the 'data folder' of the Github repo. The analysis code is distributed across several scripts. The main script is manuscript.Rmd in the 'manuscript' folder. This script calls other subordinate scripts located in the 'analysis' folder. The analyses are available in a 'reproducible container' on Code Ocean at https://doi.org/10.24433/CO.1796004.v
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