19,651 research outputs found
Supersymmetric Reciprocal Transformation and Its Applications
The supersymmetric analog of the reciprocal transformation is introduced.
This is used to establish a transformation between one of the supersymmetric
Harry Dym equations and the supersymmetric modified Korteweg-de Vries equation.
The reciprocal transformation, as a B\"{a}cklund-type transformation between
these two equations, is adopted to construct a recursion operator of the
supersymmetric Harry Dym equation. By proper factorization of the recursion
operator, a bi-Hamiltonian structure is found for the supersymmetric Harry Dym
equation. Furthermore, a supersymmetric Kawamoto equation is proposed and is
associated to the supersymmetric Sawada-Kotera equation. The recursion operator
and odd bi-Hamiltonian structure of the supersymmetric Kawamoto equation are
also constructed.Comment: 31 pages, expande
Two-qubit Quantum Logic Gate in Molecular Magnets
We proposed a scheme to realize a controlled-NOT quantum logic gate in a
dimer of exchange coupled single-molecule magnets, . We
chosen the ground state and the three low-lying excited states of a dimer in a
finite longitudinal magnetic field as the quantum computing bases and
introduced a pulsed transverse magnetic field with a special frequency. The
pulsed transverse magnetic field induces the transitions between the quantum
computing bases so as to realize a controlled-NOT quantum logic gate. The
transition rates between the quantum computing bases and between the quantum
computing bases and other excited states are evaluated and analyzed.Comment: 7 pages, 2 figure
Charge-stripe order in the electronic ferroelectric LuFe2O4
The structural features of the charge ordering states in LuFe2O4 are
characterized by in-situ cooling TEM observations from 300K down to 20K. Two
distinctive structural modulations, a major q1= (1/3, 1/3, 2) and a weak
q2=q1/10 + (0, 0, 3/2), have been well determined at the temperature of 20K.
Systematic analysis demonstrates that the charges at low temperatures are well
crystallized in a charge stripe phase, in which the charge density wave
behaviors in a non-sinusoidal fashion resulting in elemental electric dipoles
for ferroelectricity. It is also noted that the charge ordering and
ferroelectric domains often change markedly with lowering temperatures and
yields a rich variety of structural phenomena.Comment: 15 pages, 4 figure
Recommended from our members
Modeling industry 4.0 based fog computing environments for application analysis and deployment
The extension of the Cloud to the Edge of the network through Fog Computing can have a significant impact on the reliability and latencies of deployed applications. Recent papers have suggested a shift from VM and Container based deployments to a shared environment among applications to better utilize resources. Unfortunately, the existing deployment and optimization methods pay little attention to developing and identifying complete models to such systems which may cause large inaccuracies between simulated and physical run-time parameters. Existing models do not account for application interdependence or the locality of application resources which causes extra communication and processing delays. This paper addresses these issues by carrying out experiments in both cloud and edge systems with various scales and applications. It analyses the outcomes to derive a new reference model with data driven parameter formulations and representations to help understand the effect of migration on these systems. As a result, we can have a more complete characterization of the fog environment. This, together with tailored optimization methods than can handle the heterogeneity and scale of the fog can improve the overall system run-time parameters and improve constraint satisfaction. An Industry 4.0 based case study with different scenarios was used to analyze and validate the effectiveness of the proposed model. Tests were deployed on physical and virtual environments with different scales. The advantages of the model based optimization methods were validated in real physical environments. Based on these tests, we have found that our model is 90% accurate on load and delay predictions for application deployments in both cloud and edge
Non-additivity of decoherence rates in superconducting qubits
We show that the relaxation and decoherence rates 1/T_1 and 1/T_2 of a qubit
coupled to several noise sources are in general not additive, i.e., that the
total rates are not the sums of the rates due to each individual noise source.
To demonstrate this, we calculate the relaxation and pure dephasing rates 1/T_1
and 1/T_\phi of a superconducting (SC) flux qubit in the Born-Markov
approximation in the presence of several circuit impedances Z_i using network
graph theory and determine their deviation from additivity (the mixing term).
We find that there is no mixing term in 1/T_\phi and that the mixing terms in
1/T_1 and 1/T_2 can be positive or negative, leading to reduced or enhanced
relaxation and decoherence times T_1 and T_2. The mixing term due to the
circuit inductance L at the qubit transition frequency \omega_{01} is generally
of second order in \omega_{01}L/Z_i, but of third order if all impedances Z_i
are pure resistances. We calculate T_{1,2} for an example of a SC flux qubit
coupled to two impedances.Comment: 5 pages, 2 figure
Quantum Phase Diffusion in a Small Underdamped Josephson Junction
Quantum phase diffusion in a small underdamped Nb/AlO/Nb junction (
0.4 m) is demonstrated in a wide temperature range of 25-140 mK where
macroscopic quantum tunneling (MQT) is the dominant escape mechanism. We
propose a two-step transition model to describe the switching process in which
the escape rate out of the potential well and the transition rate from phase
diffusion to the running state are considered. The transition rate extracted
from the experimental switching current distribution follows the predicted
Arrhenius law in the thermal regime but is greatly enhanced when MQT becomes
dominant.Comment: 4 pages, 4 figures, 1 tabl
Interaction of Individual Skyrmions in Nanostructured Cubic Chiral Magnet
We report the direct evidence of field-dependent character of the interaction
between individual magnetic skyrmions as well as between skyrmions and edges in
B20-type FeGe nanostripes observed by means of high resolution Lorentz
transmission electron microscopy. It is shown that above certain critical
values of external magnetic field the character of such long-range skyrmion
interactions change from attraction to repulsion. Experimentally measured
equilibrium inter-skyrmion and skrymion-edge distances as function of applied
magnetic field shows quantitative agreement with the results of micromagnetic
simulations. Important role of demagnetizing fields and internal symmetry of
three-dimensional magnetic skyrmions are discussed in details.Comment: accepted in PR
On the S-matrix renormalization in effective theories
This is the 5-th paper in the series devoted to explicit formulating of the
rules needed to manage an effective field theory of strong interactions in
S-matrix sector. We discuss the principles of constructing the meaningful
perturbation series and formulate two basic ones: uniformity and summability.
Relying on these principles one obtains the bootstrap conditions which restrict
the allowed values of the physical (observable) parameters appearing in the
extended perturbation scheme built for a given localizable effective theory.
The renormalization prescriptions needed to fix the finite parts of
counterterms in such a scheme can be divided into two subsets: minimal --
needed to fix the S-matrix, and non-minimal -- for eventual calculation of
Green functions; in this paper we consider only the minimal one. In particular,
it is shown that in theories with the amplitudes which asymptotic behavior is
governed by known Regge intercepts, the system of independent renormalization
conditions only contains those fixing the counterterm vertices with
lines, while other prescriptions are determined by self-consistency
requirements. Moreover, the prescriptions for cannot be taken
arbitrary: an infinite number of bootstrap conditions should be respected. The
concept of localizability, introduced and explained in this article, is closely
connected with the notion of resonance in the framework of perturbative QFT. We
discuss this point and, finally, compare the corner stones of our approach with
the philosophy known as ``analytic S-matrix''.Comment: 28 pages, 10 Postscript figures, REVTeX4, submitted to Phys. Rev.
Dynamic marketing capabilities, foreign ownership modes, sub-national locations and the performance of foreign affiliates in developing economies
Purpose – The purpose of this paper is to examine the role of dynamic marketing capabilities (DMC), foreign ownership modes and sub-national locations on the performance of foreign owned affiliates (FOAs) in developing economies.
Design/methodology/approach – Based on a sample of 254 FOAs in Indian manufacturing sector (covering the period of 2000-2008 leading to 623 firm-year observations), the empirical paper adopts the panel data regression approach.
Findings – The study confirms the significant importance of DMC to assist FOAs to gain better sales performance in an emerging market such as India. The findings indicate that Wholly Owned Foreign Affiliates (WOFAs) have better sales performance than International Joint Venture (IJV), and Majority-owned IJV (MAIJV) perform better than Minority-owned IJV (MIIJV) in the Indian manufacturing sector. The results confirm that effective deployment of DMC leads to better sales performance in WOFAs and to some extent in MAIJVs compared to MIIJVs. Perhaps the most interesting finding is that developing DMC in non-Metropolitan areas is associated with higher sales growth than in Metropolitan locations.
Originality/value – The study contributes to the literature by examining the impact of DMC on performance of FOA by considering the organised manufacturing sector in a large and fast growing developing economy. In addition, the results for the moderating effects provide novel evidence of the conditions under which DMC of FOA interacts with different ownership modes and influence firm performance
- …