9,650 research outputs found
Fate of the Peak Effect in a Type-II Superconductor: Multicriticality in the Bragg-Glass Transition
We have used small-angle-neutron-scattering (SANS) and ac magnetic
susceptibility to investigate the global magnetic field H vs temperature T
phase diagram of a single crystal Nb in which a first-order transition of
Bragg-glass melting (disordering), a peak effect, and surface superconductivity
are all observable. It was found that the disappearance of the peak effect is
directly related to a multicritical behavior in the Bragg-glass transition.
Four characteristic phase boundary lines have been identified on the H-T plane:
a first-order line at high fields, a mean-field-like continuous transition line
at low fields, and two continuous transition line associated with the onset of
surface and bulk superconductivity. All four lines are found to meet at a
multicritical point.Comment: 4 figure
Einstein Equations and MOND Theory from Debye Entropic Gravity
Verlinde's proposal on the entropic origin of gravity is based strongly on
the assumption that the equipartition law of energy holds on the holographic
screen induced by the mass distribution of the system. However, from the theory
of statistical mechanics we know that the equipartition law of energy does not
hold in the limit of very low temperature. Inspired by the Debye model for the
equipartition law of energy in statistical thermodynamics and adopting the
viewpoint that gravitational systems can be regarded as a thermodynamical
system, we modify Einstein field equations. We also perform the study for
Poisson equation and modified Newtonian dynamics (MOND). Interestingly enough,
we find that the origin of the MOND theory can be understood from Debye
entropic gravity perspective. Thus our study may fill in the gap existing in
the literature understanding the theoretical origin of MOND theory. In the
limit of high temperature our results reduce to their respective standard
gravitational equations.Comment: 8 pages, no figures. Accepted for publication in JCA
Fe-doping induced superconductivity in charge-density-wave system 1T-TaS2
We report the interplay between charge-density-wave (CDW) and
superconductivity of 1-FeTaS ()
single crystals. The CDW order is gradually suppressed by Fe-doping,
accompanied by the disappearance of pseudogap/Mott-gap as shown by the density
functional theory (DFT) calculations. The superconducting state develops at low
temperatures within the CDW state for the samples with the moderate doping
levels. The superconductivity strongly depends on within a narrow range,
and the maximum superconducting transition temperature is 2.8 K as . We
propose that the induced superconductivity and CDW phases are separated in real
space. For high doping level (), the Anderson localization (AL) state
appears, resulting in a large increase of resistivity. We present a complete
electronic phase diagram of 1-FeTaS system that shows a
dome-like
Design and test results of different aluminum coating layers on the sCMOS sensors for soft X-ray detection
In recent years, tremendous progress has been made on complementary
metal-oxide-semiconductor (CMOS) sensors for applications as X-ray detectors.
To shield the visible light in X-ray detection, a blocking filter of aluminum
is commonly employed. We designed three types of aluminum coating layers, which
are deposited directly on the surface of back-illuminated sCMOS sensors during
fabrication. A commercial 2k * 2k sCMOS sensor is used to realize these
designs. In this work, we report their performance by comparison with that of
an uncoated sCMOS sensor. The optical transmissions at 660 nm and 850 nm are
measured, and the results show that the optical transmission reaches a level of
about 10-9 for the 200 nm aluminum layer and about 10-4 for the 100 nm aluminum
layer. Light leakage is found around the four sides of the sensor. The readout
noise, fixed-pattern noise and energy resolution of these Al-coated sCMOS
sensors do not show significant changes. The dark currents of these Al-coated
sCMOS sensors show a noticeable increase compared with that of the uncoated
sCMOS sensor at room temperatures, while no significant difference is found
when the sCMOS sensors are cooled down to about -15 degree. The aluminum
coatings show no visible crack after the thermal cycle and aging tests. Based
on these results, an aluminum coating of a larger area on larger sCMOS sensors
is proposed for future work.Comment: Accept for publication in JIns
The appraisal similarity effect: how social appraisals influence liking
The effects of cognitive appraisals on interpersonal relationships have hardly been studied. Three experiments examined how empathic social appraisal could influence liking. We tested for the appraisal similarity effect in which perceived similarity in appraisals boosts liking. In Experiment 1, perception of appraisal similarity led participants to express liking by disclosing personal contact information. This effect was replicated using a selfreport measure of liking in Experiments 2 and 3. Also, by independently manipulating attitude similarity, the appraisal similarity effect was deactivated under perceived attitude dissimilarity. Likewise, the robust attitude similarity effect was invalidated under perceived appraisal dissimilarity. In Experiment 3, the perception of validated personal beliefs mediated this interactive effect in a moderated mediation scenario, and the appraisal similarity effect
- …