publicationDate
stringlengths
1
2.79k
title
stringlengths
1
36.5k
abstract
stringlengths
1
37.3k
id
stringlengths
9
47
2023-06-26
Multiscale insight into the Cd1-xZnxTe vibrational-mechanical properties -- High-pressure experiments and ab initio calculations
The Cd1-xZnxTe semiconductor alloy is a regular system regarding its macroscopic mechanic properties in that its experimental bulk modulus exhibits a linear x-dependence, in line with ab initio predictions. Complexity arises at the bond scale, referring to the intricate Cd1-xZnxTe percolation-type Raman pattern [T. Alh...
2306.14539v1
2024-04-09
Low-Loss Silicon Directional Coupler with Arbitrary Coupling Ratios for Broadband Wavelength Operation Based on Bent Waveguides
We demonstrate a design for a high-performance $2 \times 2$ splitter meeting the essential requirements of broadband coupling, support for arbitrary coupling ratio, ultra low-loss, high fabrication tolerance, and a compact footprint. This is achieved based on a rigorous coupled mode theory analysis of the broadband r...
2404.06117v1
2002-02-01
Nonlinear Couplings Between r-modes of Rotating Neutron Stars
The r-modes of neutron stars can be driven unstable by gravitational radiation. While linear perturbation theory predicts the existence of this instability, linear theory can't provide any information about the nonlinear development of the instability. The subject of this paper is the weakly nonlinear regime of fluid d...
0202051v1
2004-08-19
Can WIMP Spin Dependent Couplings explain DAMA data, in light of Null Results from Other Experiments?
We examine whether the annual modulation found by the DAMA dark matter experiment can be explained by Weakly Interacting Massive Particles (WIMPs), in light of new null results from other experiments. CDMS II has already ruled out most WIMP-nucleus spin-independent couplings as an explanation for DAMA data. Hence we he...
0408346v3
2007-02-23
Protoplanetary Disk Turbulence Driven by the Streaming Instability: Non-Linear Saturation and Particle Concentration
We present simulations of the non-linear evolution of streaming instabilities in protoplanetary disks. The two components of the disk, gas treated with grid hydrodynamics and solids treated as superparticles, are mutually coupled by drag forces. We find that the initially laminar equilibrium flow spontaneously develops...
0702626v1
1998-05-19
Range dependence of interlayer exchange coupling
We have considered the effects of non magnetic impurities and interface roughness on the interlayer coupling between magnetic layers in metallic multilayers. The two types of defects alter the interlayer coupling in quite different ways. Elastic electron scattering by impurities in the non magnetic spacer layers betwee...
9805226v2
1999-02-09
Magnetic Properties of Zig-Zag Ladders
We analyze the phase diagram of a system of spin-1/2 Heisenberg antiferromagnetic chains interacting through a zig-zag coupling, also called zig-zag ladders. Using bosonization techniques we study how a spin-gap or more generally plateaux in magnetization curves arise in different situations. While for coupled XXZ chai...
9902112v2
1999-07-06
Model glasses coupled to two different heat baths
In a $p$-spin interaction spherical spin-glass model both the spins and the couplings are allowed to change in the course of time. The spins are coupled to a heat bath with temperature $T$, while the coupling constants are coupled to a bath having temperature $T_{J}$. In an adiabatic limit (where relaxation time of the...
9907090v1
2001-10-23
Coupled CDW and SDW Fluctuations as an Origin of Anomalous Properties of Ferromagnetic Superconductor UGe_2
It is shown that anomalous properties of UGe_2 can be understood in a unified way on the basis of a single assumption that the superconductivity is mediated by the coupled SDW and CDW fluctuations induced by the imperfect nesting of the Fermi surface with majority spins at T=T_x(P) deep in the ferromagnetic phase. Exce...
0110492v3
2002-12-16
Decoherence and gate performance of coupled solid state qubits
Solid state quantum bits are promising candidates for the realization of a {\em scalable} quantum computer. However, they are usually strongly limited by decoherence due to the many extra degrees of freedom of a solid state system. We investigate a system of two solid state qubits that are coupled via $\sigma_z^{(i)} \...
0212374v1
2003-05-14
Evolution from BCS superconductivity to Bose-Einstein condensation: Current correlation function in the broken-symmetry phase
We consider the current correlation function for a three-dimensional system of fermions embedded in a homogeneous background and mutually interacting via an attractive short-range potential, below the (superconducting) critical temperature. Diagrammatic contributions in the broken-symmetry phase are identified, that yi...
0305324v1
2003-05-28
Note on the thermodynamic Bethe Ansatz approach to the quantum phase diagram of the strong coupling ladder compounds
We investigate the low-temperature phase diagram of the exactly solved su(4) two-leg spin ladder as a function of the rung coupling $J_{\perp}$ and magnetic field $H$ by means of the thermodynamic Bethe Ansatz (TBA). In the absence of a magnetic field the model exhibits three quantum phases, while in the presence of a ...
0305633v1
2004-04-29
Strong Coupling Theory for Interacting Lattice Models
We develop a strong coupling approach for a general lattice problem. We argue that this strong coupling perspective represents the natural framework for a generalization of the dynamical mean field theory (DMFT). The main result of this analysis is twofold: 1) It provides the tools for a unified treatment of any non-lo...
0404722v2
2005-08-03
Relaxation in a glassy binary mixture: Comparison of the mode-coupling theory to a Brownian dynamics simulation
We solved the mode-coupling equations for the Kob-Andersen binary mixture using the structure factors calculated from Brownian dynamics simulations of the same system. We found, as was previously observed, that the mode-coupling temperature, Tc, inferred from simulations is about two times greater than that predicted b...
0508102v1
2005-12-23
Mode Coupling in Quantized High Quality Films
The effect of coupling of quantized modes on transport and localization in ultrathin films with quantum size effect (QSE) is discussed. The emphasis is on comparison of films with Gaussian, exponential, and power-law long-range behavior of the correlation function of surface, thickness, or bulk fluctuations. For small-...
0512614v1
2006-02-09
Spectral Properties of Holstein and Breathing Polarons
We calculate the spectral properties of the one-dimensional Holstein and breathing polarons using the self-consistent Born approximation. The Holstein model electron-phonon coupling is momentum independent while the breathing coupling increases monotonically with the phonon momentum. We find that for a linear or tight ...
0602249v1
2006-04-07
Interchain coupling effects on photoinduced phase transitions between neutral and ionic phases in an extended Hubbard model with alternating potentials and an electron-lattice coupling
Dynamics of ionic-to-neutral and neutral-to-ionic phase transitions induced by intrachain charge-transfer photoexcitations are studied in a quasi-one-dimensional extended Hubbard model with alternating potentials and an electron-lattice coupling for mixed-stack charge-transfer complexes. For interchain couplings, we us...
0604196v1
2006-10-15
Bosonization and density-matrix renormalization group studies of Fulde-Ferrell-Larkin-Ovchinnikov phase and irrational magnetization plateaus in coupled chains
We review the properties of two coupled fermionic chains, or ladders, under a magnetic field parallel to the lattice plane. Results are computed by complementary analytical (bosonization) and numerical (density-matrix renormalization group) methods which allows a systematic comparison. Limiting cases such as coupled ba...
0610397v3
2007-02-07
Crossover behavior and multi-step relaxation in a schematic model of the cut-off glass transition
We study a schematic mode-coupling model in which the ideal glass transition is cut off by a decay of the quadratic coupling constant in the memory function. (Such a decay, on a time scale tau_I, has been suggested as the likely consequence of activated processes.) If this decay is complete, so that only a linear coupl...
0702170v1
2004-07-28
Coupling of radial and non-radial oscillations of relativistic stars: gauge-invariant formalism
Linear perturbation theory is appropriate to describe small oscillations of stars, while a mild non-linearity is still tractable perturbatively but requires to consider mode coupling. It is natural to start to look at this problem by considering the coupling between linear radial and non-radial modes. Radial pulsations...
0407108v2
1992-04-08
Monte Carlo Simulations of Higgs-Fermion Systems
To gain understanding of the Higgs-fermion sector of the standard model, we study the one-component $Z_2$ symmetric and the four-component O(4) symmetric scalar models coupled to staggered fermions using the hybrid Monte Carlo algorithm. We map out the phase diagrams, and show that the $Z_2$ model has a tree level pert...
9201001v1
2004-10-25
Confinement in the lattice Landau Gauge QCD simulation
The running coupling and the Kugo-Ojima parameter of the confinement criterion are measured for the quenched SU(3) \beta=6.4, 6.45, 56^4 lattice and the unquenched \beta=5.2, 20^3 x 48 lattice of JLQCD, \beta=2.1, \kappa=0.1357, 0.1382, 24^3 x 48 lattice of CP-PACS and \beta_{imp}=6.76,a m_{u,d}=0.007, 6.83,a m_{u,d}=0...
0410038v3
1993-09-15
A Comprehensive Study of Leptoquark Bounds
We make a comprehensive study of indirect bounds on scalar leptoquarks that couple chirally and diagonally to the first generation by examining available data from low energy experiments as well as from high energy e+ e- and p pbar accelerators. The strongest bounds turn out to arise from low energy data: For leptoquar...
9309266v3
1995-12-30
R(b), R(c) and New Physics: An Updated Model Independent Analysis
We analyze LEP and SLC data from the 1995 Summer Conferences as well as from low energy neutral current experiments for signals of new physics. The reasons for doing this are twofold, first to explain the deviations from the standard model observed in $R_b$ and $R_c$ and second to constrain non-standard contributions t...
9512445v3
1998-11-20
Are there anomalous Z fermion couplings ?
The couplings of the fermions to the Z boson are of great importance in establishing the validity of the Standard Model and in looking for physics beyond it. The couplings of the b-quark to the Z boson have been the subject of much experimental study and theoretical interpretation. The apparent excess in the value of...
9811415v2
2001-03-14
Analysis of Couplings with Large Tensor Representations in SO(2N) and Proton Decay
We develop techniques for the analysis of SO(2N) invariant couplings which allow a full exhibition of the SU(N) invariant content of the spinor and tensor representations. The technique utilizes a basis consisting of a specific set of reducible SU(N) tensors in terms of which the SO(2N) invariant couplings have a simpl...
0103165v3
2004-10-29
The massive analytic invariant charge in QCD
The low energy behavior of a recently proposed model for the massive analytic running coupling of QCD is studied. This running coupling has no unphysical singularities, and in the absence of masses displays infrared enhancement. The inclusion of the effects due to the mass of the lightest hadron is accomplished by empl...
0410406v1
2005-08-14
Couplings in SO(10) Grand Unification
In this thesis, we develop techniques for the analysis of SO(2N) invariant couplings which allows a full exhibition of the SU(N) invariant content of the spinor and tensor representations. The techniques utilize a so called Basic Theorem which we first derive. Using this method an evaluation of the trilinear couplings ...
0508153v1
2006-11-30
Hard thermal loops and the entropy of supersymmetric Yang-Mills theories
We apply the previously proposed scheme of approximately self-consistent hard-thermal-loop resummations in the entropy of high-temperature QCD to N=4 supersymmetric Yang-Mills (SYM) theories and compare with a (uniquely determined) R[4,4] Pad\'e approximant that interpolates accurately between the known perturbative re...
0611393v2
1994-02-01
Field Dependent Gauge Couplings in Locally Supersymmetric Effective Quantum Field Theories
We investigate the field dependence of the gauge couplings of locally supersymmetric effective quantum field theories. We find that the Weyl rescaling of supergravity gives rise to Wess-Zumino terms that affect the gauge couplings at the one-loop level. These Wess-Zumino terms are crucial in assuring supersymmetric con...
9402005v2
1998-12-10
Asymptotic Freedom and Infrared Behavior in the Type 0 String Approach to Gauge Theory
In a recent paper we considered the type 0 string theories, obtained from the ten-dimensional closed NSR string by a GSO projection which excludes space-time fermions, and studied the low-energy dynamics of N coincident D-branes. This led us to conjecture that the four-dimensional SU(N) gauge theory coupled to 6 adjoin...
9812089v4
2006-01-29
Phase transition in matrix model with logarithmic action: Toy-model for gluons in baryons
We study the competing effects of gluon self-coupling and their interactions with quarks in a baryon, using the very simple setting of a hermitian 1-matrix model with action tr A^4 - log det(nu + A^2). The logarithmic term comes from integrating out N quarks. The model is a caricature of 2d QCD coupled to adjoint scala...
0601216v1
2006-08-25
String-inspired cosmology: Late time transition from scaling matter era to dark energy universe caused by a Gauss-Bonnet coupling
The Gauss-Bonnet (GB) curvature invariant coupled to a scalar field $\phi$ can lead to an exit from a scaling matter-dominated epoch to a late-time accelerated expansion, which is attractive to alleviate the coincident problem of dark energy. We derive the condition for the existence of cosmological scaling solutions i...
0608178v2
2004-10-15
Nonlinear theory of dust lattice mode coupling in dust crystals
Quasi-crystals formed by charged mesoscopic dust grains (dust lattices), observed since hardly a decade ago, are an exciting paradigm of a nonlinear chain. In laboratory discharge experiments, these quasi-lattices are formed spontaneously in the sheath region near a negative electrode, usually at a levitated horizontal...
0410098v1
2006-10-05
Quantum nature of a strongly-coupled single quantum dot-cavity system
Cavity quantum electrodynamics (QED) studies the interaction between a quantum emitter and a single radiation-field mode. When an atom is in strong coupling with a cavity mode1,2, it is possible to realize key quantum information processing (QIP) tasks, such as controlled coherent coupling and entanglement of distingui...
0610034v1
2007-04-19
Very weak electron-phonon coupling and strong strain coupling in manganites
The coupling of the manganite stripe phase to the lattice and to strain has been investigated via transmission electron microscopy studies of polycrystalline and thin film manganites. In polycrystalline \PCMOfiftwo a lockin to $q/a^*=0.5$ in a sample with $x>0.5$ has been observed for the first time. Such a lockin has ...
0704.2598v3
2007-07-13
The Schroedinger functional for Gross-Neveu models
Gross-Neveu type models with a finite number of fermion flavours are studied on a two-dimensional Euclidean space-time lattice. The models are asymptotically free and are invariant under a chiral symmetry. These similarities to QCD make them perfect benchmark systems for fermion actions used in large scale lattice QCD ...
0707.1939v1
2007-09-13
Rapid roll Inflation with Conformal Coupling
Usual inflation is realized with a slow rolling scalar field minimally coupled to gravity. In contrast, we consider dynamics of a scalar with a flat effective potential, conformally coupled to gravity. Surprisingly, it contains an attractor inflationary solution with the rapidly rolling inflaton field. We discuss model...
0709.1952v2
2007-10-26
Nonminimal isotropic cosmological model with Yang-Mills and Higgs fields
We establish a nonminimal Einstein-Yang-Mills-Higgs model, which contains six coupling parameters. First three parameters relate to the nonminimal coupling of non-Abelian gauge field and gravity field, two parameters describe the so-called derivative nonminimal coupling of scalar multiplet with gravity field, and the s...
0710.4992v2
2007-12-30
Depinning in a two-layer model of plastic flow
We study a model of two layers, each consisting of a d-dimensional elastic object driven over a random substrate, and mutually interacting through a viscous coupling. For this model, the mean-field theory (i.e. a fully connected model) predicts a transition from elastic depinning to hysteretic plastic depinning as diso...
0801.0137v1
2008-03-27
Single top quark production at LHC with anomalous Wtb couplings
We investigate single top production in the presence of anomalous Wtb couplings. We explicitly show that, if these couplings arise from gauge invariant effective operators, the only relevant couplings for single top production and decay are the usual gamma^mu and sigma^mu nu q_nu terms, where q is the W boson momentum....
0803.3810v3
2008-05-19
On The Uniqueness of Minimal Coupling in Higher-Spin Gauge Theory
We address the uniqueness of the minimal couplings between higher-spin fields and gravity. These couplings are cubic vertices built from gauge non-invariant connections that induce non-abelian deformations of the gauge algebra. We show that Fradkin-Vasiliev's cubic 2-s-s vertex, which contains up to 2s-2 derivatives dr...
0805.2764v2
2008-06-22
Coherence Transition of Small Josephson Junctions Coupled to a Single-Mode Resonant Cavity: Connection to the Dicke Model
We calculate the thermodynamic properties of a collection of $N$ small Josephson junctions coupled to a single-mode resonant electromagnetic cavity, at finite temperature $T$, using several approaches. In the first approach, we include all the quantum-mechanical levels of the junction, but treat the junction-cavity int...
0806.3550v1
2008-08-21
A New Method of Calculating the Running Coupling Constant
We propose a new method to compute the running coupling constant of gauge theories on the lattice. We first give the definition of the running coupling in the new scheme using the Wilson loops in a finite volume, and explain how the running of the coupling constant is extracted from the measurement of the volume depend...
0808.2875v2
2008-09-01
Strongly Coupled Radiation from Moving Mirrors and Holography in the Karch-Randall model
Motivated by the puzzles in understanding how Black Holes evaporate into a strongly coupled Conformal Field Theory, we study particle creation by an accelerating mirror. We model the mirror as a gravitating Domain Wall and consider a CFT coupled to it through gravity, in asymptotically Anti de Sitter space. This proble...
0809.0005v2
2008-11-20
Entangled photons from a strongly coupled quantum dot-cavity system
A quantum dot strongly coupled to a photonic crystal has been recently proposed as a source of entangled photon pairs [R. Johne et al., Phys. Rev. Lett. 100, 240404 (2008)]. The biexction decay via intermediate polariton states can be used to overcome the natural splitting between the exciton states coupled to the hori...
0811.3329v1
2008-12-08
Supercurrent coupling in the Faddeev-Skyrme model
Motivated by the sigma model limit of multicomponent Ginzburg-Landau theory, a version of the Faddeev-Skyrme model is considered in which the scalar field is coupled dynamically to a one-form field called the supercurrent. This coupled model is investigated in the general setting where physical space is an oriented Rie...
0812.1493v1
2008-12-16
Gate Coupling to Nanoscale Electronics
The realization of single-molecule electronic devices, in which a nanometer-scale molecule is connected to macroscopic leads, requires the reproducible production of highly ordered nanoscale gaps in which a molecule of interest is electrostatically coupled to nearby gate electrodes. Understanding how the molecule-gate ...
0812.3177v2
2009-05-19
Laser oscillation in a strongly coupled single quantum dot-nanocavity system
Strong coupling of photons and materials in semiconductor nanocavity systems has been investigated because of its potentials in quantum information processing and related applications, and has been testbeds for cavity quantum electrodynamics (QED). Interesting phenomena such as coherent exchange of a single quantum bet...
0905.3063v2
2009-11-11
Kondo screening in high-spin side-coupled two-impurity clusters
We study the system of two magnetic impurities described by a two-impurity Kondo model where only the first impurity couples directly to the conduction band, while the second impurity interacts with the first through Heisenberg exchange coupling in a "side-coupled" configuration. We consider various choices of the impu...
0911.2148v1
2009-11-29
Synchronization of coupled stochastic limit cycle oscillators
For a class of coupled limit cycle oscillators, we give a condition on a linear coupling operator that is necessary and sufficient for exponential stability of the synchronous solution. We show that with certain modifications our method of analysis applies to networks with partial, time-dependent, and nonlinear couplin...
0911.5520v2
2010-01-05
Quantum Monte-Carlo method applied to Non-Markovian barrier transmission
In nuclear fusion and fission, fluctuation and dissipation arise due to the coupling of collective degrees of freedom with internal excitations. Close to the barrier, both quantum, statistical and non-Markovian effects are expected to be important. In this work, a new approach based on quantum Monte-Carlo addressing th...
1001.0652v1
2010-01-20
Spin electric effects in molecular antiferromagnets
Molecular nanomagnets show clear signatures of coherent behavior and have a wide variety of effective low-energy spin Hamiltonians suitable for encoding qubits and implementing spin-based quantum information processing. At the nanoscale, the preferred mechanism for control of quantum systems is through application of e...
1001.3584v1
2010-01-21
Synchrotron radiation in strongly coupled conformal field theories
Using gauge/gravity duality, we compute the energy density and angular distribution of the power radiated by a quark undergoing circular motion in strongly coupled ${\cal N}=4$ supersymmetric Yang-Mills (SYM) theory. We compare the strong coupling results to those at weak coupling, and find the same angular distributio...
1001.3880v4
2010-02-22
Strong and Tunable Nonlinear Optomechanical Coupling in a Low-Loss System
A major goal in optomechanics is to observe and control quantum behavior in a system consisting of a mechanical resonator coupled to an optical cavity. Work towards this goal has focused on increasing the strength of the coupling between the mechanical and optical degrees of freedom; however, the form of this coupling ...
1002.4158v1
2010-03-10
Microwave driven arbitrary coupling between trapped charge resonances in a silicon single electron transistor
In quantum computation, information is processed by gates that must coherently couple separate qubits. In many systems the qubits are naturally coupled, but such an always-on interaction limits the algorithms that may be implemented. Coupling interactions may also be directed in devices and circuits that are provided w...
1003.2112v1
2010-03-29
Lessons from the decoupling limit of Horava gravity
We consider the so-called "healthy" extension of Horava gravity in the limit where the Stuckelberg field decouples from the graviton. We verify the alleged strong coupling problem in this limit, under the assumption that no large dimensionless parameters are put in by hand. This follows from the fact that the dispersio...
1003.5666v2
2010-06-07
A Parsing Scheme for Finding the Design Pattern and Reducing the Development Cost of Reusable Object Oriented Software
Because of the importance of object oriented methodologies, the research in developing new measure for object oriented system development is getting increased focus. The most of the metrics need to find the interactions between the objects and modules for developing necessary metric and an influential software measure ...
1006.1182v1
2010-07-18
Wormhole geometries supported by a nonminimal curvature-matter coupling
Wormhole geometries in curvature-matter coupled modified gravity are explored, by considering an explicit nonminimal coupling between an arbitrary function of the scalar curvature, R, and the Lagrangian density of matter. It is the effective stress-energy tensor containing the coupling between matter and the higher ord...
1007.3040v2
2010-07-22
Various equations for gap probabilities of coupled Gaussian matrices
Versions of Tracy-Widom (TW) and Adler-Shiota-van Moerbeke (ASvM) approaches are applied to derive various partial differential equations (PDE) satisfied by joint eigenvalue spacing probabilities of two coupled Gaussian Hermitian matrices (coupled GUE). All the lowest (third) order PDE satisfied by the probabilities fo...
1007.3793v2
2010-07-25
Quantum thermalization of two coupled two-level systems in eigenstate and bare-state representations
We study analytically the quantum thermalization of two coupled two-level systems (TLSs), which are connected with either two independent heat baths (IHBs) or a common heat bath (CHB). We understand the quantum thermalization in eigenstate and bare-state representations when the coupling between the two TLSs is stronge...
1007.4296v2
2010-07-30
Qubit-oscillator system: An analytical treatment of the ultra-strong coupling regime
We examine a two-level system coupled to a quantum oscillator, typically representing experiments in cavity and circuit quantum electrodynamics. We show how such a system can be treated analytically in the ultrastrong coupling limit, where the ratio $g/\Omega$ between coupling strength and oscillator frequency approach...
1007.5437v3
2010-08-10
A Parsing Scheme for Finding the Design Pattern and Reducing the Development Cost of Reusable Object Oriented Software
Because of the importance of object oriented methodologies, the research in developing new measure for object oriented system development is getting increased focus. The most of the metrics need to find the interactions between the objects and modules for developing necessary metric and an influential software measure ...
1008.1671v1
2010-09-06
Quantum dot Rabi rotations beyond the weak exciton-phonon coupling regime
We study the excitonic dynamics of a driven quantum dot under the influence of a phonon environment, going beyond the weak exciton-phonon coupling approximation. By combining the polaron transform and time-local projection operator techniques we develop a master equation that can be valid over a much larger range of ex...
1009.1155v2
2010-10-28
The Effect of Spatial Coupling on Compressive Sensing
Recently, it was observed that spatially-coupled LDPC code ensembles approach the Shannon capacity for a class of binary-input memoryless symmetric (BMS) channels. The fundamental reason for this was attributed to a "threshold saturation" phenomena derived by Kudekar, Richardson and Urbanke. In particular, it was shown...
1010.6020v1
2010-11-20
Instabilities in neutrino systems induced by interactions with scalars
If there are scalar particles of small or moderate mass coupled very weakly to Dirac neutrinos, in a minimal way, then neutrino-anti-neutrino clouds of sufficient number density can experience an instability in which helicities are suddenly reversed. The predicted collective evolution is many orders of magnitude faster...
1011.4585v2
2010-12-22
Counter-ions at Charged Walls: Two Dimensional Systems
We study equilibrium statistical mechanics of classical point counter-ions, formulated on 2D Euclidean space with logarithmic Coulomb interactions (infinite number of particles) or on the cylinder surface (finite particle numbers), in the vicinity of a single uniformly charged line (one single double-layer), or between...
1012.4983v1
2011-01-13
Efficiency for preforming molecules from mixtures of light Fermi and heavy Bose atoms in optical lattices: the strong-coupling-expansion method
We discuss the application of a strong-coupling expansion (perturbation theory in the hopping) for studying light-Fermi-heavy-Bose (like $^{40}$K-$^{87}$Rb) mixtures in optical lattices. We use the strong-coupling method to evaluate the efficiency for pre-forming molecules, the entropy per particle and the thermal fluc...
1101.2666v1
2011-01-21
A global hybrid coupled model based on Atmosphere-SST feedbacks
A global hybrid coupled model is developed, with the aim of studying the effects of ocean-atmosphere feedbacks on the stability of the Atlantic meridional overturning circulation. The model includes a global ocean general circulation model and a statistical atmosphere model. The statistical atmosphere model is based on...
1101.4096v5
2011-02-17
A spectral function tour of electron-phonon coupling outside the Migdal limit
We simulate spectral functions for electron-phonon coupling in a filled band system - far from the asymptotic limit often assumed where the phonon energy is very small compared to the Fermi energy in a parabolic band and the Migdal theorem predicting 1+lambda quasiparticle renormalizations is valid. These spectral func...
1102.3716v2
2011-03-01
Flavored Gauge-Mediation
The messengers of Gauge-Mediation Models can couple to standard-model matter fields through renormalizable superpotential couplings. These matter-messenger couplings generate generation-dependent sfermion masses and are therefore usually forbidden by discrete symmetries. However, the non-trivial structure of the standa...
1103.0292v2
2011-03-14
Strong and weak chaos in weakly nonintegrable many-body Hamiltonian systems
We study properties of chaos in generic one-dimensional nonlinear Hamiltonian lattices comprised of weakly coupled nonlinear oscillators, by numerical simulations of continuous-time systems and symplectic maps. For small coupling, the measure of chaos is found to be proportional to the coupling strength and lattice len...
1103.2634v2
2011-05-13
The geometry of spontaneous spiking in neuronal networks
The mathematical theory of pattern formation in electrically coupled networks of excitable neurons forced by small noise is presented in this work. Using the Freidlin-Wentzell large deviation theory for randomly perturbed dynamical systems and the elements of the algebraic graph theory, we identify and analyze the main...
1105.2801v2
2011-07-24
Optimized coupling of cold atoms into a fiber using a blue-detuned hollow-beam funnel
We theoretically investigate the process of coupling cold atoms into the core of a hollow-core photonic-crystal optical fiber using a blue-detuned Laguerre-Gaussian beam. In contrast to the use of a red-detuned Gaussian beam to couple the atoms, the blue-detuned hollow-beam can confine cold atoms to the darkest regions...
1107.4746v1
2011-09-12
The role of the indirect tunneling processes and asymmetry in couplings in orbital Kondo transport through double quantum dots
System of two quantum dots attached to external electrodes is considered theoretically in orbital Kondo regime. In general, the double dot system is coupled via both Coulomb interaction and direct hoping. Moreover, the indirect hopping processes between the dots (through the leads) are also taken into account. To inves...
1109.2621v1
2011-10-27
Couplings of light I=0 scalar mesons to simple operators in the complex plane
The flavour and glue structure of the light scalar mesons in QCD are probed by studying the couplings of the I=0 mesons $\sigma(600)$ and $f_0(980)$ to the operators $\bar{q}q$, $\alpha_s G^2$ and to two photons. The Roy dispersive representation for the $\pi\pi$ amplitude $t_0^0(s)$ is used to determine the pole posit...
1110.6074v1
2011-10-27
Disentangling multi-level systems: averaging, correlations and memory
We consider two weakly coupled systems and adopt a perturbative approach based on the Ruelle response theory to study their interaction. We propose a systematic way to parametrize the effect of the coupling as a function of only the variables of a system of interest. Our focus is on describing the impacts of the coupli...
1110.6113v1
2012-07-06
SU(3) Spin-Orbit Coupling in Systems of Ultracold Atoms
Motivated by the recent experimental success in realizing synthetic spin-orbit coupling in ultracold atomic systems, we consider N-component atoms coupled to a non-Abelian SU(N) gauge field. More specifically, we focus on the case, referred to here as "SU(3) spin-orbit-coupling," where the internal states of three-comp...
1207.1728v2
2012-07-18
Structural transitions in vertically and horizontally coupled parabolic channels of Wigner crystals
Structural phase transitions in two vertically or horizontally coupled channels of strongly interacting particles are investigated. The particles are free to move in the $x$-direction but are confined by a parabolic potential in the $y$-direction. They interact with each other through a screened power-law potential ($r...
1207.4315v1
2012-10-26
Surface superconductivity in rhombohedral graphite
We show that rhombohedral graphite may support surface superconductivity with an unusual relation between the BCS coupling constant and the order parameter. This feature results from the properties of the states localized on the graphite surfaces. In a description including only the nearest neighbour coupling of the gr...
1210.7075v2
2013-01-11
Gravitationally Coupled Dirac Equation for Antimatter
The coupling of antimatter to gravity is of general interest because of conceivable cosmological consequences ("surprises") related to dark energy and the cosmological constant. Here, we revisit the derivation of the gravitationally coupled Dirac equation and find that the prefactor of a result given previously in [D.R...
1301.2442v4
2013-01-31
Zero-lag synchronization in coupled time-delayed piecewise linear electronic circuits
We investigate and report an experimental confirmation of zero-lag synchronization (ZLS) in a system of three coupled time-delayed piecewise linear electronic circuits via dynamical relaying with different coupling configurations, namely mutual and subsystem coupling configurations. We have observed that when there is ...
1301.7588v1
2013-02-26
Bulk Stabilization, the Extra-Dimensional Higgs Portal and Missing Energy in Higgs Events
To solve the hierarchy problem, extra-dimensional models must explain why the new dimensions stabilize to the right size, and the known mechanisms for doing so require bulk scalars that couple to the branes. Because of these couplings the energetics of dimensional stabilization competes with the energetics of the Higgs...
1302.6486v1
2013-03-28
Synchronization of Weakly Coupled Oscillators: Coupling, Delay and Topology
There are three key factors of a system of coupled oscillators that characterize the interaction among them: coupling (how to affect), delay (when to affect) and topology (whom to affect). For each of them, the existing work has mainly focused on special cases. With new angles and tools, this paper makes progress in re...
1303.7248v1
2013-04-22
Displacement Convexity, A Useful Framework for the Study of Spatially Coupled Codes
Spatial coupling has recently emerged as a powerful paradigm to construct graphical models that work well under low-complexity message-passing algorithms. Although much progress has been made on the analysis of spatially coupled models under message passing, there is still room for improvement, both in terms of simplif...
1304.6026v2
2013-05-14
Planck constraints on single-field inflation
We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic oscillations, and ACT/SPT temperature data. Our analysis covers a wide variety of ...
1305.3044v2
2013-05-27
Energy Coupled Mode Theory for an arbitrary number of resonators
There is recent interest in the inter and intra element interactions of metamaterial unit cells. To calculate the effects of these interactions which can be substantial, an ab initio general coupled mode equation, in the form of an eigenvalue problem, is derived. The solution of the master equation gives the coupled fr...
1305.6085v4
2013-05-29
Epitaxial strain effects on magnetic ordering and spin-phonon couplings in the (SrMnO$_3$)$_1$/(LaMnO$_3$)$_1$ superlattice from first principles
We have studied the influence of epitaxial strain on magnetic orderings and the couplings between the spin and polar phonons in the 1:1 SrMnO$_3$/LaMnO$_3$ superlattice from first principles. Magnetic phase transitions of the superlattice induced by epitaxial strain are observed, consistent with previous reports. We fi...
1305.6943v1
2013-07-18
Driven nonlinear dynamics of two coupled exchange-only qubits
Inspired by creation of a fast exchange-only qubit (Medford et al., Phys. Rev. Lett., 111, 050501 (2013)), we develop a theory describing the nonlinear dynamics of two such qubits that are capacitively coupled, when one of them is driven resonantly at a frequency equal to its level splitting. We include conditions of s...
1307.5075v2
2013-10-17
Tunable Quantum Phase Transitions in a Resonant Level Coupled to Two Dissipative Baths
We study tunneling through a resonant level connected to two dissipative bosonic baths: one is the resistive environment of the source and drain leads, while the second comes from coupling to potential fluctuations on a resistive gate. We show that several quantum phase transitions (QPT) occur in such a model, transiti...
1310.4773v2
2013-10-22
Large Hadron Collider constraints on a light baryon number violating sbottom coupling to a top and a light quark
We investigate a model of R-parity violating (RPV) supersymmetry in which the right-handed sbottom is the lightest supersymmetric particle, and a baryon number violating coupling involving a top is the only non-negligible RPV coupling. This model evades proton decay and flavour constraints. We consider in turn each of ...
1310.6016v2
2013-10-24
Microscopic approach to coupled-channels effects on fusion
Background: Near-barrier fusion can be strongly affected by the coupling between relative motion and internal degrees of freedom of the collision partners. The time-dependent Hartree-Fock (TDHF) theory and the coupled-channels (CC) method are standard approaches to investigate this aspect of fusion dynamics. However, b...
1310.6500v2
2013-10-29
Self-Quenching of Nuclear Spin Dynamics in Central Spin Problem
We consider, in the framework of the central spin $s=1/2$ model, driven dynamics of two electrons in a double quantum dot subject to hyperfine interaction with nuclear spins and spin-orbit coupling. The nuclear subsystem dynamically evolves in response to Landau-Zener singlet-triplet transitions of the electronic subsy...
1310.7847v1
2014-01-15
Monte Carlo Study of a wide range of Molecular Spintronics Devices
Molecular spintronics devices (MSDs) are highly promising candidates for enabling quantum computation and revolutionizing computer logic and memory. An advanced MSD will require the placement of magnetic molecules between the two ferromagnetic (FM) electrodes. Recent experimental studies showed that some magnetic molec...
1401.3422v1
2014-01-28
Insensitizing exact controls for the scalar wave equation and exact controllability of $2$-coupled cascade systems of PDE's by a single control
We study the exact controllability, by a reduced number of controls, of coupled cascade systems of PDE's and the existence of exact insensitizing controls for the scalar wave equation. We give a necessary and sufficient condition for the observability of abstract coupled cascade hyperbolic systems by a single observati...
1401.7323v1
2014-02-05
Spin-orbit coupling as a source of long-range triplet proximity effect in superconductor-ferromagnet hybrid structures
We investigate the proximity effect in diffusive superconducting hybrid structures with a spin-orbit (SO) coupling. Our study is focused on the singlet-triplet conversion and the generation of long-range superconducting correlations in ferromagnetic elements. We derive the quasiclassical equations for the Green's funct...
1402.1025v3
2014-02-20
Synchronization and phase ordering in globally coupled chaotic maps
We investigate the processes of synchronization and phase ordering in a system of globally coupled maps possessing bistable, chaotic local dynamics. The stability boundaries of the synchronized states are determined on the space of parameters of the system. The collective properties of the system are characterized by m...
1402.4870v1
2014-04-02
Stabilizing Electroweak Vacuum in a Vector-like Fermion Model
To avoid possible electroweak vacuum instability in the vector-like fermion model, we introduce a new singlet scalar to the model, which couples to the vector-like fermion, and also mixes with the Higgs boson after spontaneous symmetry breaking. We investigate the vector-like fermion predominantly coupled to the third ...
1404.0681v2
2014-04-03
Constraining couplings of the top quarks to the Z boson in ttbar+Z production at the LHC
We study top quark pair production in association with a Z boson at the Large Hadron Collider (LHC) and investigate the prospects of measuring the couplings of top quarks to the Z boson. To date these couplings have not been constrained in direct measurements. Such a determination will be possible for the first time at...
1404.1005v2
2014-04-27
Pinning dynamic systems of networks with Markovian switching couplings and controller-node set
In this paper, we study pinning control problem of coupled dynamical systems with stochastically switching couplings and stochastically selected controller-node set. Here, the coupling matrices and the controller-node sets change with time, induced by a continuous-time Markovian chain. By constructing Lyapunov function...
1404.6793v1