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The Effect of Inkjet Ink Composition on Rheology And Jetting Behaviour
This work presents recent results on the way linear and non linear viscoelastic properties of the fluids affect the jetting
mechanism. Recent progress on quantitative characterising both high frequency linear (LVE) and non-linear (NLVE) viscoelasticity
of fluids allows fluids to be assessed for their jettability before using such materials in a DoD print head. In term of linear viscoelastic measurements, the Piezo Axial Vibrator (PAV) was used to probe the rheology of the fluids on a frequency range
between 10Hz and 10000Hz. A filament stretching apparatus, called the âCambridge Trimasterâ, was used in combination with
high speed cinematography, to characterize the fluids high speed stretching and break-up behaviour. The series of fluids investigated here consist in dilutions of mono disperse polystyrene with different molecular weight (110, 210, 306 and 488 kg/mol respectively) diluted in diethyl phthalate. The choice of polymer weights and concentrations were chosen to match both the
complex viscosity and the LVE. However, non linear rheological data experiments exhibit differences in the fluid relaxation time
and filament break-up mechanism. Ultra-high speed cinematography of DoD jetting events were correlated with filament break-up experiments and demonstrated that fluid rheology provides valuable information on the jetting quality of the fluids
Quantum and classical echoes in scattering systems described by simple Smale horseshoes
We explore the quantum scattering of systems classically described by binary
and other low order Smale horseshoes, in a stage of development where the
stable island associated with the inner periodic orbit is large, but chaos
around this island is well developed. For short incoming pulses we find
periodic echoes modulating an exponential decay over many periods. The period
is directly related to the development stage of the horseshoe. We exemplify our
studies with a one-dimensional system periodically kicked in time and we
mention possible experiments.Comment: 7 pages with 6 reduced quality figures! Please contact the authors
([email protected]) for an original good quality pre-prin
Spin transport through a single self-assembled InAs quantum dot with ferromagnetic leads
We have fabricated a lateral double barrier magnetic tunnel junction (MTJ)
which consists of a single self-assembled InAs quantum dot (QD) with
ferromagnetic Co leads. The MTJ shows clear hysteretic tunnel magnetoresistance
(TMR) effect, which is evidence for spin transport through a single
semiconductor QD. The TMR ratio and the curve shapes are varied by changing the
gate voltage.Comment: 4 pages, 3 figure
Epitaxial growth and the magnetic properties of orthorhombic YTiO3 thin films
High-quality YTiO3 thin films were grown on LaAlO3 (110) substrates at low
oxygen pressures (<10-8 Torr) using pulsed laser deposition. The in-plane
asymmetric atomic arrangements at the substrate surface allowed us to grow
epitaxial YTiO3 thin films, which have an orthorhombic crystal structure with
quite different a- and b-axes lattice constants. The YTiO3 film exhibited a
clear ferromagnetic transition at 30 K with a saturation magnetization of about
0.7 uB/Ti. The magnetic easy axis was found to be along the [1-10] direction of
the substrate, which differs from the single crystal easy axis direction, i.e.,
[001].Comment: 14 pages, 4 figure
Initial nucleon structure results with chiral quarks at the physical point
We report initial nucleon structure results computed on lattices with 2+1
dynamical M\"obius domain wall fermions at the physical point generated by the
RBC and UKQCD collaborations. At this stage, we evaluate only connected quark
contributions. In particular, we discuss the nucleon vector and axial-vector
form factors, nucleon axial charge and the isovector quark momentum fraction.
From currently available statistics, we estimate the stochastic accuracy of the
determination of and to be around 10%, and we expect to
reduce that to 5% within the next year. To reduce the computational cost of our
calculations, we extensively use acceleration techniques such as low-eigenmode
deflation and all-mode-averaging (AMA). We present a method for choosing
optimal AMA parameters.Comment: 7 pages, 11 figures; talk presented at the 32nd International
Symposium on Lattice Field Theory, 23-28 June, 2014, Columbia University, New
York, US
Scanning tunneling spectroscopic studies of the pairing state of cuprate superconductors
Quasiparticle tunneling spectra of both hole-doped (p-type) and electron-doped (n-type) cuprates are studied using a low-temperature scanning tunneling microscope. The results reveal that neither the pairing symmetry nor the pseudogap phenomenon is universal among all cuprates, and that the response of n-type cuprates to quantum impurities is drastically different from that of the p-type cuprates. The only ubiquitous features among all cuprates appear to be the strong electronic correlation and the nearest-neighbor antiferromagnetic Cu2+-Cu2+ coupling in the CuO2 planes
Partially composite 2-Higgs-doublet model
In the extra dimensional scenarios with gauge fields in the bulk, the
Kaluza-Klein (KK) gauge bosons can induce Nambu-Jona-Lasinio (NJL) type
attractive four-fermion interactions, which can break electroweak symmetry
dynamically with accompanying composite Higgs fields. We consider a possibility
that electroweak symmetry breaking (EWSB) is triggered by both a fundamental
Higgs and a composite Higgs arising in a dynamical symmetry breaking mechanism
induced by a new strong dynamics. The resulting Higgs sector is a partially
composite two-Higgs doublet model with specific boundary conditions on the
coupling and mass parameters originating at a compositeness scale .
The phenomenology of this model is discussed including the collider
phenomenology at LHC and ILC.Comment: To appear in the proceeding of LCWS06, Bangalore, Indi
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