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47
1993-09-22
Symmetry properties of SU3 vector coupling coefficients
A presentation of the problem of calculating the vector coupling coefficients for $SU3 \supset SU2 \otimes U1$ is made, in the spirit of traditional treatments of SU2 coupling. The coefficients are defined as the overlap matrix element between product states and a coupled state with good SU3 quantum numbers. A techniqu...
9309023v1
1999-03-30
A program for coupled-channels calculations with all order couplings for heavy-ion fusion reactions
A FORTRAN77 program is presented that calculates fusion cross sections and mean angular momenta of the compound nucleus under the influence of couplings between the relative motion and several nuclear collective motions. The no-Coriolis approximation is employed to reduce the dimension of coupled-channels equations. Th...
9903074v1
2004-09-06
Gauge symmetric delta(1232) couplings and the radiative muon capture in hydrogen
Using the difference between the gauge symmetric and standard pi-N-delta couplings, a contact pi-pi-N-N term, quadratic in the pi-N-delta coupling, is explicitly constructed. Besides, a contribution from the delta excitation mechanism to the photon spectrum for the radiative muon capture in hydrogen is derived from the...
0409011v1
2004-06-18
Accurate calculations of magnetic dipole and electric quadrupole hyperfine coupling constants of 6 P_{3/2} state of Cesium atom : A Relativistic Coupled Cluster approach
We report the magnetic dipole and electric quadrupole hyperfine coupling constants of 6 P_{3/2} state of ^{133} Cs(I= {7/2}) obtained from the relativistic coupled cluster (RCC) method. To our knowledge, no prior electric quadrupole hyperfine CC calculation is available for ^{133} Cs(6 P_{3/2}) state. Our computed magn...
0406083v1
2004-11-26
On linear coupling of acoustic and cyclotron waves in plasma flows
It is found that in magnetized electrostatic plasma flows the velocity shear couples ion-acoustic waves with ion-cyclotron waves and leads, under favorable conditions, to their efficient reciprocal transformations. It is shown that in a two-dimensional setup this coupling has a remarkable feature: it is governed by equ...
0411235v1
2005-06-10
Coupled-mode theory for periodic side-coupled microcavity and photonic crystal structures
We use a phenomenological Hamiltonian approach to derive a set of coupled mode equations that describe light propagation in waveguides that are periodically side-coupled to microcavities. The structure exhibits both Bragg gap and (polariton like) resonator gap in the dispersion relation. The origin and physical signifi...
0506102v1
2006-05-19
Coupled applications on distributed resources
Coupled models are set to become increasingly important in all aspects of science and engineering as tools with which to study complex systems in an integrated manner. Such coupled, hybrid simulations typically communicate data between the component models of which they are comprised relatively infrequently, and so a G...
0605171v1
1998-01-23
Transverse-mode coupling in a Kerr medium
We analyze nonlinear transverse mode coupling in a Kerr medium placed in an optical cavity and its influence on bistability and different kinds of quantum noise reduction. Even for an input beam that is perfectly matched to a cavity mode, the nonlinear coupling produces an excess noise in the fluctuations of the output...
9801053v1
2004-03-31
Effect of intersubsystem coupling on the geometric phase in a bipartite system
The influence of intersubsystem coupling on the cyclic adiabatic geometric phase in bipartite systems is investigated. We examine the geometric phase effects for two uniaxially coupled spin$-{1/2}$ particles, both driven by a slowly rotating magnetic field. It is demonstrated that the relation between the geometric pha...
0403231v2
2004-07-07
Quantum state transfer in imperfect artificial spin networks
High-fidelity quantum computation and quantum state transfer are possible in short spin chains. We exploit a system based on a dispersive qubit-boson interaction to mimic XY coupling. In this model, the usually assumed nearest-neighbors coupling is no more valid: all the qubits are mutually coupled. We analyze the perf...
0407058v2
2005-03-08
The Partition Function for the Anharmonic Oscillator in the Strong-Coupling Regime
We consider a single anharmonic oscillator with frequency $\omega$ and coupling constant $\lambda$ respectively, in the strong-coupling regime. We are assuming that the system is in thermal equilibrium with a reservoir at temperature $\beta^{-1}$. Using the strong-coupling perturbative expansion, we obtain the partitio...
0503080v1
2005-10-20
Overdamping by weakly coupled environments
A quantum system weakly interacting with a fast environment usually undergoes a relaxation with complex frequencies whose imaginary parts are damping rates quadratic in the coupling to the environment, in accord with Fermi's ``Golden Rule''. We show for various models (spin damped by harmonic-oscillator or random-matri...
0510164v1
2006-05-01
Nonlinear coupling of nano mechanical resonators to Josephson quantum circuits
We propose a technique to couple the position operator of a nano mechanical resonator to a SQUID device by modulating its magnetic flux bias. By tuning the magnetic field properly, either linear or quadratic couplings can be realized, with a discretely adjustable coupling strength. This provides a way to realize cohere...
0605017v1
2007-03-22
Controlled-NOT gate design for Josephson phase qubits with tunable inductive coupling: Weyl chamber steering and area theorem
Superconducting qubits with tunable coupling are ideally suited for fast and accurate implementation of quantum logic. Here we present a simple approach, based on Weyl chamber steering, to CNOT gate design for inductively coupled phase qubits with tunable coupling strength g. In the presence of simultaneous rf pulses o...
0703208v1
1999-02-12
A critical Ising model on the Labyrinth
A zero-field Ising model with ferromagnetic coupling constants on the so-called Labyrinth tiling is investigated. Alternatively, this can be regarded as an Ising model on a square lattice with a quasi-periodic distribution of up to eight different coupling constants. The duality transformation on this tiling is conside...
9902009v1
2007-05-27
Electromagnetic field quantization in an anisotropic and inhomogeneous magnetodielectric
The electromagnetic field in an anisotropic and inhomogeneous magnetodielectric is quantized by modelling the medium with two independent quantum fields. Some coupling tensors coupling the electromagnetic field with the medium are introduced. Electric and magnetic polarizations are obtained in terms of the ladder opera...
0705.3942v1
2007-06-09
Coupling of Optical Lumped Nanocircuit Elements and Effects of Substrates
We present here a model for the coupling among small nanoparticles excited by an optical electric field in the framework of our optical lumped nanocircuit theory [N. Engheta, A. Salandrino, and A. Alu Phys. Rev. Lett. 95, 095504 (2005)]. We derive how this coupling affects the corresponding nanocircuit model by adding ...
0706.1316v1
2007-06-15
Electron-acoustic-phonon scattering and electron relaxation in two-coupled quantum rings
Electron relaxation, induced by acoustic phonons, is studied for coupled quantum rings in the presence of external fields, both electric and magnetic. We address the problem of a single electron in vertically coupled GaAs quantum rings. Electron-phonon interaction is accounted for both deformation potential and piezoel...
0706.2352v1
2007-07-27
Zero delay synchronization of chaos in coupled map lattices
We show that two coupled map lattices that are mutually coupled to one another with a delay can display zero delay synchronization if they are driven by a third coupled map lattice. We analytically estimate the parametric regimes that lead to synchronization and show that the presence of mutual delays enhances synchron...
0707.4051v1
2007-08-31
Continuation of solutions of coupled dynamical systems
Recently, the synchronization of coupled dynamical systems has been widely studied. Synchronization is referred to as a process wherein two (or many) dynamical systems are adjusted to a common behavior as time goes to infinity, due to coupling or forcing. Therefore, before discussing synchronization, a basic problem on...
0708.4275v1
2007-09-22
Interactions of Hermitian and non-Hermitian Hamiltonians
The coupling of non-Hermitian PT-symmetric Hamiltonians to standard Hermitian Hamiltonians, each of which individually has a real energy spectrum, is explored by means of a number of soluble models. It is found that in all cases the energy remains real for small values of the coupling constant, but becomes complex if t...
0709.3605v1
2007-09-24
Environmental Dependence of Masses and Coupling Constants
We construct a class of scalar field models coupled to matter that lead to the dependence of masses and coupling constants on the ambient matter density. Such models predict a deviation of couplings measured on the Earth from values determined in low-density astrophysical environments, but do not necessarily require th...
0709.3825v3
2007-10-11
Optical coupling of fundamental whispering gallery modes in bi-spheres
What will happen if two identical microspheres, with fundamental whispering gallery modes excited in each of them, become optically coupled? Conventional wisdom based on coupled-mode arguments says that two new modes, bonding and anti-bonding, with two split frequencies would be formed. In this paper we demonstrate, us...
0710.2276v1
2007-11-19
Critical Lattice Size Limit for Synchronized Chaotic State in 1-D and 2-D Diffusively Coupled Map Lattices
We consider diffusively coupled map lattices with $P$ neighbors (where $P$ is arbitrary) and study the stability of synchronized state. We show that there exists a critical lattice size beyond which the synchronized state is unstable. This generalizes earlier results for nearest neighbor coupling. We confirm the analyt...
0711.2851v1
2008-02-19
Coupled oscillators as models of quintom dark energy
We investigate quintom cosmology in FRW universes using isomorphic models consisting of three coupled oscillators, one of which carries negative kinetic energy. In particular, we examine the cosmological paradigms of minimally-coupled massless quintom, of two conformally-coupled massive scalars and of conformally-coupl...
0802.2595v2
2008-03-14
Kondo effect in quantum dots coupled to ferromagnetic leads with noncollinear magnetizations: effects due to electron-phonon coupling
Spin-polarized transport through a quantum dot strongly coupled to ferromagnetic electrodes with non-collinear magnetic moments is analyzed theoretically in terms of the non-equilibrium Green function formalism. Electrons in the dot are assumed to be coupled to a phonon bath. The influence of electron-phonon coupling o...
0803.2152v1
2008-06-03
Hyperbolicity of the Trace Map for the Weakly Coupled Fibonacci Hamiltonian
We consider the trace map associated with the Fibonacci Hamiltonian as a diffeomorphism on the invariant surface associated with a given coupling constant and prove that the non-wandering set of this map is hyperbolic if the coupling is sufficiently small. As a consequence, for these values of the coupling constant, th...
0806.0645v1
2008-06-10
Higher Order Periodic Solutions of Coupled phi4 Models
We obtain several higher order exact periodic solutions of (i) a coupled symmetric phi4 model in an external field, (ii) an asymmetric coupled phi4 model, (iii) an asymmetric-symmetric coupled phi4 model, in terms of Lame polynomials of order two and obtain the corresponding hyperbolic solutions in the appropriate limi...
0806.1564v1
2008-09-05
Time-delayed feedback in neurosystems
The influence of time delay in systems of two coupled excitable neurons is studied in the framework of the FitzHugh-Nagumo model. Time-delay can occur in the coupling between neurons or in a self-feedback loop. The stochastic synchronization of instantaneously coupled neurons under the influence of white noise can be d...
0809.1025v1
2008-10-17
Non-minimal coupling in inflation and inflating with the Higgs boson
We analyse the effect of the non-minimal coupling of the form $\xi\phi^2R/2$ on the single field inflation. If the non-minimal coupling is large, it relaxes the constraint on the field self coupling, making it possible to use the Standard Model Higgs field as the inflaton. At the same time, even small non-minimal coupl...
0810.3165v1
2008-10-27
Analysis of Firing Behaviors in Networks of Pulse-Coupled Oscillators with Delayed Excitatory Coupling
For networks of pulse-coupled oscillators with delayed excitatory coupling, we analyze the firing behaviors depending on coupling strength and transmission delay. The parameter space consisting of strength and delay is partitioned into two regions. For one region, we derive a low bound of interspike intervals, from whi...
0810.4798v1
2008-11-21
Conditions for synchronizability in arrays of coupled linear systems
Synchronization control in arrays of identical output-coupled continuous-time linear systems is studied. Sufficiency of new conditions for the existence of a synchronizing feedback law are analyzed. It is shown that for neutrally stable systems that are detectable form their outputs, a linear feedback law exists under ...
0811.3530v1
2008-11-22
Approximation of quantum graph vertex couplings by scaled Schrödinger operators on thin branched manifolds
We discuss approximations of vertex couplings of quantum graphs using families of thin branched manifolds. We show that if a Neumann type Laplacian on such manifolds is amended by suitable potentials, the resulting Schr\"odinger operators can approximate non-trivial vertex couplings. The latter include not only the del...
0811.3707v1
2008-12-09
Probe of anomalous neutrino couplings to W and Z in medium energy setup of a beta-beam facility
Capability of medium energy setup of a beta beam experiment to probe new physics contributions to neutrino-W and neutrino-Z couplings are investigated. We employ the effective lagrangian approach of Buchmuller and Wyler and obtain 95% confidence level limits on neutrino couplings to these gauge bosons without assuming ...
0812.1722v2
2009-02-18
Scalar-tensor theories with pseudoscalar couplings
We consider the scalar-tensor theories of gravity extended by the pseudoscalar couplings to matter and gauge fields and derive constraints on the CP-odd combinations of scalar and pseudoscalar couplings from laboratory spin precession experiments and from the evolution of photon polarization over cosmological distances...
0902.3217v1
2009-02-25
A parallel splitting method for weakly coupled monotone inclusions
A parallel splitting method is proposed for solving systems of coupled monotone inclusions in Hilbert spaces. Convergence is established for a wide class of coupling schemes. Unlike classical alternating algorithms, which are limited to two variables and linear coupling, our parallel method can handle an arbitrary numb...
0902.4415v1
2009-04-01
Decay of Rabi oscillations by dipolar-coupled dynamical spin environments
We investigate the Rabi oscillations decay of a spin decohered by a spin bath whose internal dynamics is caused by dipolar coupling between the bath spins. The decay form and rate as a function of the intra-bath coupling is studied analytically, and confirmed numerically. The decay in general has neither exponential/Ga...
0904.0263v1
2009-04-16
Large $N_c$ Expansion and the Parity Violating $π, N, Δ$ Couplings
In the limit of large $N_c$ we first consider the $N_c$ ordering of the various parity violating $\pi, N, \Delta$ couplings. Then we derive the relations among these couplings and consistency relations from the stability of these couplings under the chiral loop corrections with and without the mass splitting between $N...
0904.2418v1
2009-04-27
Rigorous derivation of the Kinetic/Fluid coupling involving a Kinetic layer on a toy problem
In this article, we investigate the kinetic/fluid coupling on a toy model. We obtain it rigorously from a hydrodynamical limit. The idea is that at the level of the full kinetic model, the coupling is obvious. We then investigate the coupling obtained when passing into the limit. We show that, especially in presence of...
0904.4199v1
2009-05-14
Relaxation of Josephson qubits due to strong coupling to two-level systems
We investigate the energy relaxation (T1) process of a qubit coupled to a bath of dissipative two-level fluctuators (TLF). We consider the fluctuators strongly coupled to the qubit both in the limit of spectrally separated single TLF's as well as in the limit of spectrally dense TLF's. We conclude that the avoided leve...
0905.2332v3
2009-05-19
Hyperbolicity of the Trace Map for a Strongly Coupled Quasiperiodic Schrodinger Operator
We consider the trace map associated with the silver ratio Schrodinger operator as a diffeomorphism on the invariant surface associated with a given coupling constant and prove that the non-wandering set of this map is hyperbolic if the coupling is sufficiently large. As a consequence, for this values of the coupling c...
0905.3082v1
2009-08-20
Theory of anisotropic exchange in laterally coupled quantum dots
The effects of spin-orbit coupling on the two-electron spectra in lateral coupled quantum dots are investigated analytically and numerically. It is demonstrated that in the absence of magnetic field the exchange interaction is practically unaffected by spin-orbit coupling, for any interdot coupling, boosting prospects ...
0908.2961v2
2009-09-13
Co-coupled synchronization of fractional-order unified chaotic systems
Synchronization of fractional-order chaotic systems is a hot topic in the field of nonlinear study. The co-coupled synchronization between two fractional-order chaotic systems with different initial conditions is investigated in this paper. Based on Lyapunov stability principle and Gerschgorin theorem, the co-coupled s...
0909.2410v1
2009-09-15
Adaptive coupling for achieving stable synchronization of chaos
We consider synchronization of coupled chaotic systems and propose an adaptive strategy that aims at evolving the strength of the coupling to achieve stability of the synchronized evolution. We test this idea in a simple configuration in which two chaotic systems are unidirectionally coupled (a sender and a receiver) a...
0909.2896v2
2009-11-16
Exchange coupling in transition-metal nano-clusters on Cu(001) and Cu(111) surfaces
We present results of density-functional calculations on the magnetic properties of Cr, Mn, Fe and Co nano-clusters (1 to 9 atoms large) supported on Cu(001) and Cu(111). The inter-atomic exchange coupling is found to depend on competing mechanisms, namely ferromagnetic double exchange and antiferromagnetic kinetic exc...
0911.3004v1
2009-11-16
Quintessence with quadratic coupling to dark matter
We introduce a new form of coupling between dark energy and dark matter that is quadratic in their energy densities. Then we investigate the background dynamics when dark energy is in the form of exponential quintessence. The three types of quadratic coupling all admit late-time accelerating critical points, but these ...
0911.3089v1
2010-01-13
Strong and weak coupling of two coupled qubits
I investigate the dynamics and power spectrum of two coupled qubits (two-level systems) under incoherent continuous pump and dissipation. New regimes of strong coupling are identified, that are due to additional paths of coherence flow in the system. Dressed states are reconstructed even in the regime of strong decoher...
1001.2201v1
2010-02-05
An analytic Pade-motivated QCD coupling
We consider a modification of the Minimal Analytic (MA) coupling of Shirkov and Solovtsov. This modified MA (mMA) coupling reflects the desired analytic properties of the space-like observables. We show that an approximation by Dirac deltas of its discontinuity function $\rho$ is equivalent to a Pad\'e (rational) appro...
1002.1264v1
2010-03-04
Resonant coupling of a Bose-Einstein condensate to a micromechanical oscillator
We report experiments in which the vibrations of a micromechanical oscillator are coupled to the motion of Bose-condensed atoms in a trap. The interaction relies on surface forces experienced by the atoms at about one micrometer distance from the mechanical structure. We observe resonant coupling to several well-resolv...
1003.1126v1
2010-04-09
Superconducting Qubits Coupled to Torsional Resonators
We propose a scheme of strong and tunable coupling between a superconducting phase qubit and nanomechanical torsional resonator. In our scheme the torsional resonator directly modulates the largest energy scale (the Josephson coupling energy) of the phase qubit, and the coupling strength is very large. We analyze the q...
1004.1497v2
2010-07-02
Higher Derivative Brane Couplings from T-Duality
The Wess-Zumino coupling on D-branes in string theory is known to receive higher derivative corrections which couple the Ramond-Ramond potential to terms involving the square of the spacetime curvature tensor. Consistency with T-duality implies that the branes should also have four-derivative couplings that involve the...
1007.0441v2
2010-09-22
Coupling Circuit Resonators Among Themselves and To Nitrogen-Vacancy Centers in Diamond
We propose a scheme to couple NV centers in diamond through coplanar waveguide resonators. The central conductor of the resonator is split into several pieces which are coupled strongly with each other via simple capacitive junctions or superconducting Josephson junctions. The NV centers are then put at the junctions. ...
1009.4314v2
2010-12-01
Size dependent electric voltage-controlled magnetic anisotropy in multiferroic heterostructures: Interface-charge and strain co-mediated magnetoelectric coupling
We present a phenomenological scheme to study the size-dependent electric voltage-controlled magnetic anisotropy in ferromagnetic (FM)/ferroelectric (FE) heterostructures. The FM layers are either metallic Fe(001), Ni(001), Co(0001), or half-metallic (La, Sr)MnO3 films. Two magnetoelectric mechanisms, i.e., interface-c...
1012.0088v1
2010-12-17
Holographic superconductor models in the non-minimal derivative coupling theory
We study a general class of holographic superconductor models via the St\"{u}ckelberg mechanism in the non-minimal derivative coupling theory in which the charged scalar field is kinetically coupling to Einstein's tensor. We explore the effects of the coupling parameter on the critical temperature, the order of phase t...
1012.3820v1
2011-01-06
All Possible Coupling Schemes in XY Spin Chains for Perfect State Transfer
We investigate quantum state transfer in XY spin chains and propose a recursive procedure to construct the nonuniform couplings of these chains with arbitrary length to achieve perfect state transfer(PST). We show that this method is capable of finding all possible coupling schemes for PST. These schemes, without exter...
1101.1156v1
2011-02-24
Spatially Coupled LDPC Codes for Decode-and-Forward in Erasure Relay Channel
We consider spatially-coupled protograph-based LDPC codes for the three terminal erasure relay channel. It is observed that BP threshold value, the maximal erasure probability of the channel for which decoding error probability converges to zero, of spatially-coupled codes, in particular spatially-coupled MacKay-Neal c...
1102.5087v2
2011-03-17
Heat transport and thermal rectification in quasi-one-dimensional systems
In this work we investigate heat conduction along a ladder-model conformed by two coupled one dimensional lattices with different anharmonicity. We study how the interchain coupling modifies the thermal properties of the isolated systems. For a large enough coupling strength, we demonstrate that a harmonic lattice inte...
1103.3443v1
2011-03-31
Emergent patterns in a spin-orbit coupled spin-2 Bose-Einstein condensate
The ground-state phases of a spin-orbit (SO) coupled atomic spin-2 Bose-Einstein condensate (BEC) are studied. Interesting density patterns spontaneously formed are widespread due to the competition between SO coupling and spin-dependent interactions like in a SO coupled spin-1 condensate. Unlike the case of spin-1 con...
1103.6074v1
2011-06-07
Coupling of polaritons to vibrational modes of ultracold atoms in an optical lattice
The coupling of internal electronic excitations to vibrational modes of the external motion of ultracold atoms in an optical lattice is studied here in using a perturbation expansion in small atomic displacements. In the Mott insulator case with one atom per site, the resonance dipole-dipole coupling between neighborin...
1106.1272v1
2011-07-23
Electroweak effective couplings for future precision experiments
The leading hadronic effects in electroweak theory derive from vacuum polarization which are non-perturbative hadronic contributions to the running of the gauge couplings, the electromagnetic alpha_{em}(s) and the SU(2)_L coupling alpha_2(s). I will report on my recent package "alphaQED", which besides the effective fi...
1107.4683v1
2011-09-09
Covering relations for coupled map networks
Following [6,12], we study coupled map networks over arbitrary finite graphs. An estimate from below for a topological entropy of a perturbed coupled map network via a topological entropy of an unperturbed network by making use of the covering relations for coupled map networks is obtained. The result is quite general,...
1109.1931v1
2011-09-09
Standard Model gauge coupling unification
We study the low energy evolution of coupling constants of the standard model and show that gauge coupling unification can be achieved at the electroweak scale with a suitable normalization. We choose the grand unification group to be the semidirect product of Spin(8) by S_3. In this case the three low energy gauge cou...
1109.2052v3
2011-09-12
A note on the coupling of the techni-dilaton to the weak bosons
In this note, we study the coupling of the techni-dilaton to the weak bosons. We consider two cases: (1) The dilaton directly couples to the weak bosons similarly to the SM. (2) The coupling in question is effectively induced only through the techni-fermion loops. In both cases, we find that the coupling is essentially...
1109.2554v3
2011-09-18
A Coupling Argument for the Random Transposition Walk
This paper explores the mixing time of the random transposition walk on the symmetric group. While it has long been known that this walk mixes in order n*log(n) time, this result has not previously been attained using coupling. A coupling argument showing the correct order mixing time is presented. This is accomplished...
1109.3915v1
2011-10-20
Search for anomalous Wtb couplings in single top quark production in ppbar collisions at sqrt(s) = 1.96 TeV
We present new direct constraints on a general $Wtb$ interaction using data corresponding to an integrated luminosity of 5.4 fb$^{-1}$ collected by the D0 detector at the Tevatron $p\bar{p}$ collider. The standard model provides a purely left-handed vector coupling at the $Wtb$ vertex, while the most general, lowest di...
1110.4592v2
2012-02-16
Ground state and excitation spectra of a strongly correlated lattice by the coupled cluster method
We apply Coupled Cluster Method to a strongly correlated lattice and develop the Spectral Coupled Cluster equations by finding an approximation to the resolvent operator, that gives the spectral response for an certain class of probe operators. We apply the method to a $MnO_2$ plane model with a parameters choice which...
1202.3537v3
2012-02-29
Dipole Coupling Effect of Holographic Fermion in Charged Dilatonic Gravity
In this note, we study the dipole coupling effect of holographic fermion in a charged dilatonic black hole proposed by Gubser and Rocha (arXiv:0911.2898). It is found that the property of Fermi liquid is rigid under perturbation of dipole coupling, and the Fermi momentum is linearly shifted. A gap is dynamically genera...
1202.6539v1
2012-03-09
Dynamical locality of the nonminimally coupled scalar field and enlarged algebra of Wick polynomials
We discuss dynamical locality in two locally covariant quantum field theories, the nonminimally coupled scalar field and the enlarged algebra of Wick polynomials. We calculate the relative Cauchy evolution of the enlarged algebra, before demonstrating that dynamical locality holds in the nonminimally coupled scalar fie...
1203.2151v1
2012-07-11
Enhancing Synchrony in Chaotic Oscillators by Dynamic Relaying
In a chain of mutually coupled oscillators, the coupling threshold for synchronization between the outermost identical oscillators decreases when a type of impurity (in terms of parameter mismatch) is introduced in the inner oscillator(s). The outer oscillators interact indirectly via dynamic relaying, mediated by the ...
1207.2563v1
2012-08-29
Radio-frequency spectroscopy of weakly bound molecules in spin-orbit coupled atomic Fermi gases
We investigate theoretically radio-frequency spectroscopy of weakly bound molecules in an ultracold spin-orbit-coupled atomic Fermi gas. We consider two cases with either equal Rashba and Dresselhaus coupling or pure Rashba coupling. The former system has been realized very recently at Shanxi University [Wang et al., a...
1208.5841v1
2012-09-12
Highly efficient coupling of photons from nanoemitters into single-mode optical fibers
Highly efficient coupling of photons from nanoemitters into single-mode optical fibers is demonstrated using tapered fibers. 7.4 +/- 1.2 % of the total emitted photons from single CdSe/ZnS nanocrystals were coupled into a 300-nm-diameter tapered fiber. The dependence of the coupling efficiency on the taper diameter was...
1209.2474v1
2012-10-01
Electron-phonon superconductivity and charge density wave instability in the layered titanium-based pnictide BaTi$_2$Sb$_2$O
I present the results of first principles calculations of the phonon dispersions and electron-phonon coupling for BaTi$_2$Sb$_2$O. The phonon dispersions show a weak lattice instability near the zone corners that leads to a charge-density wave phase. The calculations of the electron-phonon coupling reveal strong coupli...
1210.0499v2
2012-10-27
Theory of electromechanical coupling in dynamical graphene
We study the coupling between mechanical motion and Dirac electrons in a dynamical sheet of graphene. We show that this coupling can be understood in terms of an effective gauge field acting on the electrons, which has two contributions: quasistatic and purely dynamic of the Berry-phase origin. As is well known, the st...
1210.7384v1
2012-11-27
Bootstrap and momentum transfer dependence in small x evolution equations
Using Monte Carlo integration techniques, we investigate running coupling effects compatible with the high energy bootstrap condition to all orders in the strong coupling in evolution equations valid at small values of Bjorken x in deep inelastic scattering. A model for the running of the coupling with analytic behavio...
1211.6332v1
2012-12-04
Selectable linear or quadratic coupling in an optomechanical system
There has been much interest recently in the analysis of optomechanical systems incorporating dielectric nano- or microspheres inside a cavity field. We analyse here the situation when one of the mirrors of the cavity itself is also allowed to move. We reveal that the interplay between the two oscillators yields a cros...
1212.0641v1
2012-12-12
Coupling mechanism between microscopic two-level system and superconducting qubits
We propose a scheme to clarify the coupling nature between superconducting Josephson qubits andmicroscopic two-level systems. Although dominant interest in studying two-level systems was in phase qubits previously, we find that the sensitivity of the generally used spectral method in phase qubits is not sufficient to e...
1212.2687v1
2012-12-16
Sensitivity enhancement in optical micro-tube resonator sensors via mode coupling
A liquid filled, low refractive index material inner-coated silica micro-tube has been proposed and studied as a coupled micro-resonator sensor to greatly enhance biochemical sensor sensitivity. Its unique coupling phenomenon has been analyzed and utilized to boost the refractive index sensitivity of the device to 967n...
1212.3851v1
2013-01-24
A Potential Theory of General Spatially-Coupled Systems via a Continuum Approximation
This paper analyzes general spatially-coupled (SC) systems with multi-dimensional coupling. A continuum approximation is used to derive potential functions that characterize the performance of the SC systems. For any dimension of coupling, it is shown that, if the boundary of the SC systems is fixed to the unique stabl...
1301.5728v2
2013-02-03
Invertible coupled KdV and coupled Harry Dym hierarchies
In this paper we discuss the conditions under which the coupled KdV and coupled Harry Dym hierarchies possess inverse (negative) parts. We further investigate the structure of nonlocal parts of tensor invariants of these hierarchies, in particular, the nonlocal terms of vector fields, conserved one-forms, recursion ope...
1302.0526v1
2013-02-18
Controlled coupling of photonic crystal cavities using photochromic tuning
We present a method to control the resonant coupling interaction in a coupled-cavity photonic crystal molecule by using a local and reversible photochromic tuning technique. We demonstrate the ability to tune both a two-cavity and a three-cavity photonic crystal molecule through the resonance condition by selectively t...
1302.4322v1
2013-02-27
Ferromagnetic to antiferromagnetic transition of one-dimensional spinor Bose gases with spin-orbit coupling
We have analytically solved one-dimensional interacting two-component bosonic gases with spin-orbit (SO) coupling by the Bethe-ansatz method. Through a gauge transformation, the effect of SO coupling is incorporated into a spin-dependent twisted boundary condition. Our result shows that the SO coupling can influence th...
1302.6901v2
2013-03-15
Exact black hole solution for scale dependent gravitational couplings and the corresponding coupling flow
We study a black hole solution for the generalized Einstein Hilbert action with scale dependent couplings G(r) and Lambda(r). The form of the couplings is not imposed, but rather deduced from the existence of a non trivial symmetrical solution. A classical-like choice of the integration constants is found. Finally, the...
1303.3892v1
2013-04-12
Probing Anomalous HZZ Couplings at the LHeC
We examine the sensitivity to the couplings of the Higgs boson to neutral gauge bosons in a model independent way at the Large Hadron electron Collider (LHeC). We have obtained the constraints on anomalous couplings for $HZZ$ vertex via the process $e^{-}p\rightarrow e^{-}HqX$. We find the accessible limits of the anom...
1304.3616v2
2013-04-29
Coupled-channel scattering in 1+1 dimensional lattice model
Based on the Lippmann-Schwinger equation approach, a generalized L\"uscher's formula in 1+1 dimensions for two particles scattering in both the elastic and coupled-channel cases in moving frames is derived. A 2D coupled-channel scattering lattice model is presented, the model represents a two-coupled-channel resonant s...
1304.7812v1
2013-05-08
Physics at the ILC with focus mostly on Higgs physics
Physics at the ILC is reviewed focusing mostly on Higgs physics. It is emphasized that at the ILC it is possible to measure the $hZZ$ coupling totally model independently, which in turn allows model-independent normalization of various branching ratio measurements and consequently the absolute measurements of correspon...
1305.1692v2
2013-05-26
Nonlinearity Induced Critical Coupling
We study a critically coupled system (Opt. Lett., \textbf{32}, 1483 (2007)) with a Kerr-nonlinear spacer layer. Nonlinearity is shown to inhibit null-scattering in a critically coupled system at low powers. However, a system detuned from critical coupling can exhibit near-complete suppression of scattering by means of ...
1305.5983v1
2013-05-29
Light scattering from coupled plasmonic nanospheres on a substrate
An efficient numerical method based on half-space Green function and spherical harmonics expansion is used to study the light scattering from coupled multiple nanospheres on a substrate. The ellipsometric spectra for various geometries of coupled Au nanospheres are calculated and analyzed to realize the effects of plas...
1305.6764v1
2013-12-11
Spin-orbit coupling in quantum gases
Spin-orbit coupling links a particle's velocity to its quantum mechanical spin, and is essential in numerous condensed matter phenomena, including topological insulators and Majorana fermions. In solid-state materials, spin-orbit coupling originates from the movement of electrons in a crystal's intrinsic electric field...
1312.3292v1
2014-01-10
Delay-induced patterns in a two-dimensional lattice of coupled oscillators
We show how a variety of stable spatio-temporal periodic patterns can be created in 2D-lattices of coupled oscillators with non-homogeneous coupling delays. A "hybrid dispersion relation" is introduced, which allows studying the stability of time-periodic patterns analytically in the limit of large delay. The results a...
1401.2325v1
2014-01-09
Coherent Electronic Coupling in Atomically Thin MoSe2
We report the first direct spectroscopic evidence for coherent electronic coupling between excitons and trions in atomically thin transition metal dichalcogenides, specifically monolayer MoSe2. Signatures of coupling appear as isolated cross-peaks in two-color pump-probe spectra, and the lineshape of the peaks reveals ...
1401.2909v1
2014-01-24
Properties of spatial coupling in compressed sensing
In this paper we address a series of open questions about the construction of spatially coupled measurement matrices in compressed sensing. For hardware implementations one is forced to depart from the limiting regime of parameters in which the proofs of the so-called threshold saturation work. We investigate quantitat...
1401.6380v1
2014-02-03
Coupling constants of bottom (charmed) mesons with pion from three point QCD sum rules
In this article, the three point QCD sum rules is used to compute the strong coupling constants of vertices containing the strange bottomed ( charmed ) mesons with pion. The coupling constants are calculated, when both the bottom ( charm ) and pion states are off-shell. A comparison of the obtained results of coupling ...
1402.0296v1
2014-02-06
Dynamics and non-equilibrium steady state in a system of coupled harmonic oscillators
A system of two coupled oscillators, each of them coupled to an independent reservoir, is analysed. The analytical solution of the non-rotating wave master equation is obtained in the high-temperature and weak coupling limits. No thermal entanglement is found in the high-temperature limit. In the weak coupling limit th...
1402.1477v1
2014-04-01
Optimal rectification by strongly coupled spins
We study heat transport in a pair of strongly coupled spins. In particular, we present a condition for optimal rectification, i.e., flow of heat in one direction and complete isolation in the opposite direction. We show that the strong-coupling formalism is necessary for correctly describing heat flow in a wide range o...
1404.0348v2
2014-04-14
From inflation to late time acceleration with a decaying vacuum coupled to radiation or matter
We consider General Relativity with matter and radiation, one of these fluids being coupled to vacuum. We find that Universe dynamics starts by an inflation phase if the coupled fluid has a negative energy density at early time. Then, there is always a finite scale factor singularity but when vacuum and matter are coup...
1404.3518v1
2014-07-15
Quantum model of coupled intersubband plasmons
We present a quantum model to calculate the dipole-dipole coupling between electronic excitations in the conduction band of semiconductor quantum wells. We demonstrate that the coupling depends on a characteristic length, related to the overlap between microscopic current densities associated with each electronic excit...
1407.3923v1
2014-07-22
Current-driven dynamics of coupled domain walls in a synthetic antiferromagnet
We develop the theory of magnetic domain wall motion in coupled double-layer systems where electrons can hop between the layers giving rise to an antiferromagnetic coupling. We demonstrate that the force from the interlayer coupling drives the walls and the effect of the extrinsic pinning is greatly reduced if the doma...
1407.5805v1
2014-07-30
Stability of the shadow projection and the left-curtain coupling
The (left-)curtain coupling, introduced by Beiglb\"ock and the author is an extreme element of the set of "martingale" couplings between two real probability measures in convex order. It enjoys remarkable properties with respect to order relations and a minimisation problem inspired by the theory of optimal transport. ...
1407.8009v2
2014-09-27
Complete achromatic optical switching between two waveguides with a sign flip of the phase mismatch
We present a two-waveguide coupler which, realizes complete achromatic all-optical switching. The coupling of the waveguides has a hyperbolic-secant shape while the phase mismatch has a sign flip at the maximum of the coupling. We derive an analytic solution for the electric field propagation using coupled mode theory ...
1409.7757v1
2014-10-19
Monotonicity of Avoidance Coupling on $K_N$
Answering a question by Angel, Holroyd, Martin, Wilson and Winkler, we show that the maximal number of non-colliding coupled simple random walks on the complete graph $K_N$, which take turns, moving one at a time, is monotone in $N$. We use this fact to couple $\lceil \frac N4 \rceil$ such walks on $K_N$, improving the...
1410.5032v2