Search results for "SCALE"
showing 10 items of 5180 documents
Bulk-free topological insulator Bi 2 Se 3 nanoribbons with magnetotransport signatures of Dirac surface states
2018
Many applications for topological insulators (TIs) as well as new phenomena require devices with reduced dimensions. While much progress has been made to realize thin films of TIs with low bulk carrier density, nanostructures have not yet been reported with similar properties, despite the fact that size confinement should help reduce contributions from bulk carriers. Here we demonstrate that Bi2Se3 nanoribbons, grown by a simple catalyst-free physical-vapour deposition, have inherently low bulk carrier densities, and can be further made bulk-free by size confinement, thus revealing the high mobility topological surface states. Magneto transport and Hall conductance measurements, in single n…
A Fractional Approach to Non-Newtonian Blood Rheology in Capillary Vessels
2019
In small arterial vessels, fluid mechanics involving linear viscous fluid does not reproduce experimental results that correspond to non-parabolic profiles of velocity across the vessel diameter. In this paper, an alternative approach is pursued introducing long-range interactions that describe the interactions of non-adjacent fluid volume elements due to the presence of red blood cells and other dispersed cells in plasma. These non-local forces are defined as linearly dependent on the product of the volumes of the considered elements and on their relative velocity. Moreover, as the distance between two volume elements increases, the non-local forces decay with a material distance-decaying …
Nonlinear Evolution Equations, Quasi-Solitons and their Experimental Manifestation
1990
We review the typical experimental facts which characterize quasisolitons in one-dimensional real systems, in connection with their modeling by nonlinear partial differential equations.We consider these nonlinear waves or excitations in two different domains of the real world : the macroworld and the microworld. In the macroworld we examine typical one-dimensional devices : the electrical networks, the Josephson transmission lines and the optical fibers, where the localized waves or pulses can be simply and coherently created, easily observed and manipulated on a macroscopic scale. In the microworld, we consider the magnetic chains and polymers, where the indirect experimental signatures of…
Unduland universe: expansion with alternating eras of acceleration and deceleration
2005
If the equation of state for 'dark energy' varies periodically, the expansion of the Universe may have undergone alternating eras of acceleration and deceleration. We examine a specific form that survives existing observational tests, does not single out the present state of the Universe as exceptional, and suggests a future much like the matter-dominated past: a smooth expansion without a final inflationary epoch.
μ-e conversion in nuclei and Z' physics
1993
Together with the existence of new neutral gauge bosons, models based on extended gauge groups (rank > 4) often predict also new charged fermions. A mixing of the known fermions with new states with exotic weak-isospin assignments (left-handed singlets and right-handed doublets) will induce tree level flavour changing neutral interactions mediated by Z exchange, while if the mixing is only with new states with ordinary weak-isospin assignments, the flavour changing neutral currents are mainly due to the exchange of the lightest new neutral gauge boson Z'. We show that the present experimental limits on μ-e conversion in nuclei give a nuclear-model-independent bound on the Z-e-μ vertex which…
Measure dependence of 2D simplicial quantum gravity
1995
We study pure 2D Euclidean quantum gravity with $R^2$ interaction on spherical lattices, employing Regge's formulation. We attempt to measure the string susceptibility exponent $\gamma_{\rm str}$ by using a finite-size scaling Ansatz in the expectation value of $R^2$. To check on effects of the path integral measure we investigate two scale invariant measures, the "computer" measure $dl/l$ and the Misner measure $dl/\sqrt A$.
High-resolution study of Gamow-Teller excitations in theCa42(He3,t)Sc42reaction and the observation of a “low-energy super-Gamow-Teller state”
2015
Y. Fujita et al.; 15 pags.; 6 figs.; 7 tabs.; PACS number(s): 21.10.Hw, 25.55.Kr, 27.40.+z, 25.40.Ep
Time-of-flight photoelectron emission microscopy TOF-PEEM: first results
1998
The time structure of the synchrotron radiation at BESSY (Berlin) is used to operate a photoemission electron microscope in a time-of-flight (TOF) mode. The electrons which are emitted from the sample surface with different energies are dispersed in a drift tube subsequent to the imaging optics. The screen of the microscope was replaced by a fast scintillator (tau = 1.4 ns) and the light is detected by an ultra fast gated intensified CCD camera (800 ps gate 1 MHz repetition rate). The resolving power in the energy domain is demonstrated and possible implications on the spatial resolution (chromatic correction) are discussed. Additionally, an improved contrast at very low emission energies i…
EFFECTIVE FIELD THEORY APPROACH TO THE NUCLEON–NUCLEON INTERACTION REVISITED
2006
It is argued that Weinberg's approach to the nucleon–nucleon (NN) interaction problem within effective field theory provides a consistent power counting for renormalized diagrams. Within this scheme the NN potential is organized as an expansion in terms of small quantities like small external momenta and the pion mass (divided by the characteristic large scale of the effective theory). Physical observables to any given order in these small quantities are calculated from the solutions of the Lippmann–Schwinger (or Schrödinger) equation.
Bounds on the triplet fermions in type-III seesaw and implications for collider searches
2021
Type-III seesaw is a simple extension of the Standard Model~(SM) with the SU$(2)_\text{L}$ triplet fermion with zero hypercharge. It can explain the origin of the tiny neutrino mass and flavor mixing. After the electroweak symmetry breaking the light neutrino mass is generated by the seesaw mechanism which further ensures the mixings between the light neutrino and heavy neutral lepton mass eigenstates. If the triplet fermions are around the electroweak scale having sizable mixings with the SM sector allowed by the correct gauge symmetry, they can be produced at the high energy colliders leaving a variety of characteristic signatures. Based on a simple and concrete realizations of the model …