2,160 research outputs found
Single-electron latch with granular film charge leakage suppressor
A single-electron latch is a device that can be used as a building block for
Quantum-dot Cellular Automata (QCA) circuits. It consists of three nanoscale
metal "dots" connected in series by tunnel junctions; charging of the dots is
controlled by three electrostatic gates. One very important feature of a
single-electron latch is its ability to store ("latch") information represented
by the location of a single electron within the three dots. To obtain latching,
the undesired leakage of charge during the retention time must be suppressed.
Previously, to achieve this goal, multiple tunnel junctions were used to
connect the three dots. However, this method of charge leakage suppression
requires an additional compensation of the background charges affecting each
parasitic dot in the array of junctions. We report a single-electron latch
where a granular metal film is used to fabricate the middle dot in the latch
which concurrently acts as a charge leakage suppressor. This latch has no
parasitic dots, therefore the background charge compensation procedure is
greatly simplified. We discuss the origins of charge leakage suppression and
possible applications of granular metal dots for various single-electron
circuits.Comment: 21 pages, 4 figure
Stability of Landau-Ginzburg branes
We evaluate the ideas of Pi-stability at the Landau-Ginzburg point in moduli
space of compact Calabi-Yau manifolds, using matrix factorizations to B-model
the topological D-brane category. The standard requirement of unitarity at the
IR fixed point is argued to lead to a notion of "R-stability" for matrix
factorizations of quasi-homogeneous LG potentials. The D0-brane on the quintic
at the Landau-Ginzburg point is not obviously unstable. Aiming to relate
R-stability to a moduli space problem, we then study the action of the gauge
group of similarity transformations on matrix factorizations. We define a naive
moment map-like flow on the gauge orbits and use it to study boundary flows in
several examples. Gauge transformations of non-zero degree play an interesting
role for brane-antibrane annihilation. We also give a careful exposition of the
grading of the Landau-Ginzburg category of B-branes, and prove an index theorem
for matrix factorizations.Comment: 46 pages, LaTeX, summary adde
The economic characteristic of products and services in the sphere of communications and informatization
The basic economic characteristics of products and services in the sphere of communication and informatization are considered in the article
Evolution equation of quantum tomograms for a driven oscillator in the case of the general linear quantization
The symlectic quantum tomography for the general linear quantization is
introduced. Using the approach based upon the Wigner function techniques the
evolution equation of quantum tomograms is derived for a parametric driven
oscillator.Comment: 11 page
Deformation theory of objects in homotopy and derived categories III: abelian categories
This is the third paper in a series. In part I we developed a deformation
theory of objects in homotopy and derived categories of DG categories. Here we
show how this theory can be used to study deformations of objects in homotopy
and derived categories of abelian categories. Then we consider examples from
(noncommutative) algebraic geometry. In particular, we study noncommutative
Grassmanians that are true noncommutative moduli spaces of structure sheaves of
projective subspaces in projective spaces.Comment: Alexander Efimov is a new co-author of this paper. Besides some minor
changes, a new part (part 3) about noncommutative Grassmanians was adde
Semiorthogonal decompositions of derived categories of equivariant coherent sheaves
Let X be an algebraic variety with an action of an algebraic group G. Suppose
X has a full exceptional collection of sheaves, and these sheaves are invariant
under the action of the group. We construct a semiorthogonal decomposition of
bounded derived category of G-equivariant coherent sheaves on X into
components, equivalent to derived categories of twisted representations of the
group. If the group is finite or reductive over the algebraically closed field
of zero characteristic, this gives a full exceptional collection in the derived
equivariant category. We apply our results to particular varieties such as
projective spaces, quadrics, Grassmanians and Del Pezzo surfaces.Comment: 28 pages, uses XY-pi
Structure of 2-Methyl-5,6,7-triphenyl-6,7-dihydropyrazolo[2,3-\u3cem\u3ea\u3c/em\u3e]pyrimidine
C25H21N3, Mr = 363.46, monoclinic, P21/n, a = 9.245 (2), b = 23.502 (5), c = 9.340 (2) Å, β= 103.50(3)°, V=1973.3(2) Å3, Z=4, Dx= 1.220 (2) g cm-3, λ (Mo Kα )= 0.71069 Å, μ = 0.068 cm-1, F(000) = 768, T= 292 K, R = 0.091 for 1442 unique observed reflections. The dihydropyrimidine ring adopts a distorted sofa conformation. The aryl substituents on the saturated C atoms have an axial orientation
Deformation theory of objects in homotopy and derived categories II: pro-representability of the deformation functor
This is the second paper in a series. In part I we developed deformation
theory of objects in homotopy and derived categories of DG categories. Here we
extend these (derived) deformation functors to an appropriate bicategory of
artinian DG algebras and prove that these extended functors are
pro-representable in a strong sense.Comment: Alexander Efimov is a new co-author of this paper. New material was
added: A_{\infty}-structures, Maurer-Cartan theory for A_{\infty}-algebras.
This allows us to strengthen our main results on the pro-representability of
pseudo-functors coDEF_{-} and DEF_{-}. We also obtain an equivalence between
homotopy and derived deformation functors under weaker hypothese
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