Results for "Stefan Heun"

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Ohmic contact engineering in few-layer black Phosphorus field effect transistorsMay 14 2019Achieving good quality Ohmic contacts to van der Waals materials is a challenge, since at the interface between metal and van der Waals material, different conditions can occur, ranging from the presence of a large energy barrier between the two materials ... More
Aharonov-Bohm interferometer based on n-p junction in graphene nanoribbonsOct 15 2015Aug 20 2016We demonstrate that the phenomenon of current confinement along graphene n-p junctions at high magnetic fields can be used to form an Aharonov-Bohm interferometer. The interference system exploits a closed n-p junction that can be induced by a floating ... More
Tuning hydrogen adsorption on graphene by gate voltageMay 06 2019In order to realize applications of hydrogen-adsorbed graphene, a main issue is how to control hydrogen adsorption/desorption at room temperature. In this study, we demonstrate the possibility to tune hydrogen adsorption on graphene by applying a gate ... More
Hydrogen storage with titanium-functionalized grapheneDec 05 2013We report on hydrogen adsorption and desorption on titanium-covered graphene in order to test theoretical proposals to use of graphene functionalized with metal atoms for hydrogen storage. At room temperature titanium islands grow with an average diameter ... More
Low-temperature quantum transport in CVD-grown single crystal grapheneMar 24 2016Chemical vapor deposition (CVD) has been proposed for large-scale graphene synthesis for practical applications. However, the inferior electronic properties of CVD graphene are one of the key problems to be solved. In this study, we present a detailed ... More
Impact of electron heating on the equilibration between quantum Hall edge channelsDec 12 2011When two separately contacted quantum Hall (QH) edge channels are brought into interaction, they can equilibrate their imbalance via scattering processes. In the present work we use a tunable QH circuit to implement a junction between co-propagating edge ... More
Manipulating quantum Hall edge channels in graphene through Scanning Gate MicroscopyJul 10 2017Oct 12 2017We show evidence of the backscattering of quantum Hall edge channels in a narrow graphene Hall bar, induced by the gating effect of the conducting tip of a Scanning Gate Microscope, which we can position with nanometer precision. We show full control ... More
Li-intercalated Graphene on SiC(0001): an STM studyJun 05 2017We present a systematical study via scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED) on the effect of the exposure of Lithium (Li) on graphene on silicon carbide (SiC). We have investigated Li deposition both on epitaxial ... More
Correlation between morphology and transport properties of quasi-free-standing monolayer grapheneSep 01 2014Nov 19 2014We investigate the morphology of quasi-free-standing monolayer graphene (QFMLG) formed at several temperatures by hydrogen intercalation and discuss its relationship with transport properties. Features corresponding to incomplete hydrogen intercalation ... More
The role of water in the preparation and stabilization of high quality phosphorene flakesNov 13 2015Water is believed to be harmful for the stability of phosphorene.On the contrary, the presence of small amount of water allows the synthesis of high-quality material in liquid exfoliation of black phosphorus using dimethylsulfoxide as solvent. A phosphorus/water ... More
Full electrostatic control of quantum interference in an extended trenched Josephson junctionMar 07 2019Hybrid semiconductor/superconductor devices constitute an important platform for a wide range of applications, from quantum computing to topological-state-based architectures. Here, we demonstrate full modulation of the interference pattern in a superconducting ... More
Hybrid 2D Black Phosphorus/Polymer Materials: New Platforms for Device FabricationFeb 04 2018Hybrid materials, containing a 2D filler embedded in a polymeric matrix, are an interesting platform for several applications, because of the variety of properties that the filler can impart to the polymer matrix when dispersed at the nanoscale. Moreover, ... More
Surface structures of graphene covered Cu (103)Sep 04 2018We studied the surface structures of chemical vapor deposited (CVD) graphene on Cu(103). The graphene covered Cu surface had (103) facets parallel to the Cu[010] direction, on which triangular patterns were formed. In contrast, the bare Cu surface showed ... More
Tuning of quantum interference in top-gated graphene on SiCNov 28 2013We report on quantum-interference measurements in top-gated Hall bars of monolayer graphene epitaxially grown on the Si face of SiC, in which the transition from negative to positive magnetoresistance was achieved varying temperature and charge density. ... More
Revealing the nature of defects in quasi free standing mono-layer graphene on SiC(0001) by means of Density Functional TheoryOct 11 2017Quasi free standing monolayer graphene (QFMLG) grown on SiC by selective Si evaporation from the Si-rich SiC(0001) face and H intercalation displays irregularities in STM and AFM analysis, appearing as localized features, which we previously identified ... More
Quantum Hall Effect in a Josephson JunctionMay 08 2018Hybrid superconductor/semiconductor devices constitute a powerful platform where intriguing topological properties can be investigated. Here we present fabrication methods and analysis of Josephson junctions formed by a high-mobility InAs quantum-well ... More
Decoration of exfoliated black phosphorus with nickel nanoparticles and application in catalysisSep 16 2016Aug 28 2017Nickel nanoparticles were dispersed on the surface of exfoliated black phosphorus and the resulting nanohybrid Ni/2DBP showed an improved stability respect to pristine 2D BP when kept in ambient conditions in the darkness. Ni/2DBP was applied as catalyst ... More
Layer-resolved imaging of domain wall interactions in magnetic tunnel junction-like trilayersFeb 27 2007Nov 08 2007We have performed a layer-resolved, microscopic study of interactions between domain walls in two magnetic layers separated by a non-magnetic one, using high-resolution x-ray photoemission electron microscopy. Domain walls in the hard magnetic Co layer ... More
The Influence of Graphene Curvature on Hydrogen Adsorption: Towards Hydrogen Storage DevicesNov 28 2013The ability of atomic hydrogen to chemisorb on graphene makes the latter a promising material for hydrogen storage. Based on scanning tunneling microscopy techniques, we report on site-selective adsorption of atomic hydrogen on convexly curved regions ... More
A sensitive calorimetric technique to study energy (heat) exchange at the nano-scaleApr 29 2019Every time a chemical reaction occurs, an energy exchange between reactants and environment exists, which is defined as the enthalpy of the reaction. In the last decades, research has resulted in an increasing number of devices at the micro- or nano-scale. ... More
Revealing the multi-bonding state between hydrogen and graphene-supported Ti clustersAug 03 2016Hydrogen adsorption on graphene-supported metal clusters has brought much controversy due to the complex nature of the bonding between hydrogen and metal clusters. The bond types of hydrogen and graphene-supported Ti clusters are experimentally and theoretically ... More
Atomic and Electronic Structure of Si Dangling Bonds in Quasi-Free-Standing Monolayer GrapheneJun 05 2017Si dangling bonds without H termination at the interface of quasi-free standing monolayer graphene (QFMLG) are known scattering centers that can severely affect carrier mobility. In this report, we study the atomic and electronic structure of Si dangling ... More
Scanning Gate Imaging of quantum point contacts and the origin of the 0.7 AnomalyNov 25 2013Sep 04 2014The origin of the anomalous transport feature appearing at conductance G \approx 0.7 x (2e2/h) in quasi-1D ballistic devices - the so-called 0.7 anomaly - represents a long standing puzzle. Several mechanisms were proposed to explain it, but a general ... More
Imaging backscattering through impurity-induced antidots in quantum Hall constrictionsSep 11 2012We exploit the biased tip of a scanning gate microscope (SGM) to induce a controlled backscattering between counter-propagating edge channels in a wide constriction in the quantum Hall regime. We compare our detailed conductance maps with a numerical ... More
Spatially-resolved analysis of edge-channel equilibration in quantum Hall circuitsFeb 21 2011We demonstrate an innovative quantum Hall circuit with variable geometry employing the moveable electrostatic potential induced by a biased atomic force microscope tip. We exploit this additional degree of freedom to identify the microscopic mechanisms ... More
Noncovalent functionalization of few-layer black phosphorus with metal nanoparticles and its application in catalysisSep 16 2016Transition metal nanoparticles of Ni, Pd, Ru and Au, each of them stabilized by a suitable capping agent, were dispersed on the surface of few-layer black phosphorus (2D BP) achieving new nanocomposite 2D materials. Ni nanoparticles supported on 2D BP ... More
Imaging fractional incompressible stripes in integer quantum Hall systemsMay 02 2012Transport experiments provide conflicting evidence on the possible existence of fractional order within integer quantum Hall systems. In fact integer edge states sometimes behave as monolithic objects with no inner structure, while other experiments clearly ... More
Enhanced ambient stability of exfoliated black phosphorus by passivation with nickel nanoparticlesAug 01 2019Since its discovery, the environmental instability of exfoliated black phosphorus (2D bP) has emerged as a challenge that hampers its wide application in chemistry, physics, and materials science. Many studies have been carried out to overcome this drawback. ... More
Rapid CVD growth of millimetre-sized single crystal graphene using a cold-wall reactorJan 26 2015In this work we present a simple pathway to obtain large single-crystal graphene on copper (Cu) foils with high growth rates using a commercially available cold-wall chemical vapour deposition (CVD) reactor. We show that graphene nucleation density is ... More
Revealing the atomic structure of the buffer layer between SiC(0001) and epitaxial grapheneNov 21 2011Aug 02 2013On the SiC(0001) surface (the silicon face of SiC), epitaxial graphene is obtained by sublimation of Si from the substrate. The graphene film is separated from the bulk by a carbon-rich interface layer (hereafter called the buffer layer) which in part ... More
Inter-Edge Backscattering in Buried Split-Gate-Defined Graphene Quantum Point ContactsAug 26 2016Quantum Hall effects offer a formidable playground for the investigation of quantum transport phenomena. Edge modes can be detected, branched, and mixed by designing a suitable potential landscape in a two-dimensional conducting system subject to a strong ... More
Polymer-based black phosphorus (bP) hybrid materials by in situ radical polymerization: an effective tool to exfoliate bP and stabilize bP nanoflakesApr 11 2018Black phosphorus (bP) has been recently investigated for next generation nanoelectronic multifunctional devices. However, the intrinsic instability of exfoliated bP (the bP nanoflakes) towards both moisture and air has so far overshadowed its practical ... More
MBE growth of self-assisted InAs nanowires on grapheneOct 03 2016Self-assisted growth of InAs nanowires on graphene by molecular beam epitaxy is reported. Nanowires with diameter of ~50 nm and aspect ratio of up to 100 were achieved. The morphological and structural properties of the nanowires were carefully studied ... More
Bilayer-induced asymmetric quantum Hall effect in epitaxial grapheneOct 08 2014Oct 14 2014The transport properties of epitaxial graphene on SiC(0001) at quantizing magnetic fields are investigated. Devices patterned perpendicularly to SiC terraces clearly exhibit bilayer inclusions distributed along the substrate step edges. We show that the ... More
Efficient n-type Doping in Epitaxial Graphene through Strong Lateral Orbital Hybridization of Ti AdsorbateMar 18 2016Aug 23 2016In recent years, various doping methods for epitaxial graphene have been demonstrated through atom substitution and adsorption. Here we observe by angle-resolved photoemission spectroscopy (ARPES) a coupling-induced Dirac cone renormalization when depositing ... More
Finite-Size Corrections for Ground States of Edwards-Anderson Spin GlassesOct 28 2011May 30 2012Extensive computations of ground state energies of the Edwards-Anderson spin glass on bond-diluted, hypercubic lattices are conducted in dimensions d=3,..,7. Results are presented for bond-densities exactly at the percolation threshold, p=p_c, and deep ... More
Superstability of the yeast cell cycle dynamics: Ensuring causality in the presence of biochemical stochasticityMay 05 2006Gene regulatory dynamics is governed by molecular processes and therefore exhibits an inherent stochasticity. However, for the survival of an organism it is a strict necessity that this intrinsic noise does not prevent robust functioning of the system. ... More
Weak Limit of the 3-State Quantum Walk on the LineApr 04 2014May 21 2014We revisit the one dimensional discrete time quantum walk with 3 states and the Grover coin. We derive analytic expressions for observed the localization, an long time approximation for the probability density function (PDF). We also connect the time ... More
Streaming KernelizationMay 06 2014Kernelization is a formalization of preprocessing for combinatorially hard problems. We modify the standard definition for kernelization, which allows any polynomial-time algorithm for the preprocessing, by requiring instead that the preprocessing runs ... More
On the commutability of homogenization and linearization in finite elasticityNov 16 2010May 16 2011We study non-convex elastic energy functionals associated to (spatially) periodic, frame indifferent energy densities with a single non-degenerate energy well at SO(n). Under the assumption that the energy density admits a quadratic Taylor expansion at ... More
The midpoint between dipole and parton showersJun 16 2015Sep 19 2015We present a new parton-shower algorithm. Borrowing from the basic ideas of dipole cascades, the evolution variable is judiciously chosen as the transverse momentum in the soft limit. This leads to a very simple analytic structure of the evolution. A ... More
Interactive Natural Language Acquisition in a Multi-modal Recurrent Neural ArchitectureMar 24 2017Feb 07 2018For the complex human brain that enables us to communicate in natural language, we gathered good understandings of principles underlying language acquisition and processing, knowledge about socio-cultural conditions, and insights about activity patterns ... More
Stochastic mortality models: An infinite dimensional approachJul 11 2019Demographic projections of future mortality rates involve a high level of uncertainty and require stochastic mortality models. The current paper investigates forward mortality models driven by a (possibly infinite dimensional) Wiener process and a compensated ... More
Reliability of regulatory networks and its evolutionMay 27 2008The problem of reliability of the dynamics in biological regulatory networks is studied in the framework of a generalized Boolean network model with continuous timing and noise. Using well-known artificial genetic networks such as the repressilator, we ... More
Reliability of genetic networks is evolvableJul 10 2007Control of the living cell functions with remarkable reliability despite the stochastic nature of the underlying molecular networks -- a property presumably optimized by biological evolution. We here ask to what extent the property of a stochastic dynamical ... More
On Semigroups of Two-Dimensional Upper-Triangular Integer MatricesMay 13 2019We analyze algorithmic problems in finitely generated semigroups of two-dimensional upper-triangular integer matrices. These semigroup problems are tightly connected with problems about compositions of affine functions over one variable. Building on a ... More
Black Phosphorus/Palladium Nanohybrid: Unraveling the Nature of P-Pd Interaction and Application in Selective HydrogenationMar 06 2019The burgeoning interest in 2D black phosphorus (bP) contributes to expand its applications in countless fields. In the present study, 2D bP is used as a support for homogeneously dispersed palladium nanoparticles directly grown on it by a wet chemical ... More
The H-Covariant Strong Picard GroupoidSep 08 2004Apr 25 2005The notion of H-covariant strong Morita equivalence is introduced for *-algebras over C = R(i) with an ordered ring R which are equipped with a *-action of a Hopf *-algebra H. This defines a corresponding H-covariant strong Picard groupoid which encodes ... More
A shortcut to (sun)flowers: Kernels in logarithmic space or linear timeApr 30 2015We investigate whether kernelization results can be obtained if we restrict kernelization algorithms to run in logarithmic space. This restriction for kernelization is motivated by the question of what results are attainable for preprocessing via simple ... More
Non-Classical Longitudinal Magneto-Resistance in Anisotropic Black PhosphorusAug 02 2018Dec 05 2018Resistivity measurements of a few-layer black phosphorus (bP) crystal in parallel magnetic fields up to 45 T are reported as a function of the angle between the in-plane field and the source-drain (S-D) axis of the device. The crystallographic directions ... More
A Perspective on Recent Advances in Phosphorene Functionalization and its Application in DevicesMar 28 2019Phosphorene, the 2D material derived from black phosphorus, has recently attracted a lot of interest for its properties, suitable for applications in material science. In particular, the physical features and the prominent chemical reactivity on its surface ... More
Investigation of surface homogeneity of (3200) PhaethonDec 05 2018Time-series multi-band photometry and spectrometry were performed in Nov.-Dec. 2017 to investigate the homogeneity of the surface of asteroid (3200) Phaethon. We found that Phaethon is a B-type asteroid, in agreement with previous studies, and that it ... More
Analytical model of a 3D beam dynamics in a wakefield deviceFeb 19 2018Feb 14 2019In this paper we suggest an analytic model, and derive simple formulas, for the beam dynamics in a wakefield structure of arbitrary cross-section. The results could be applied to estimate an upper limit of the projected beam size in devices such as the ... More
A filtering technique for Markov chains with applications to spectral embeddingNov 05 2014Spectral methods have proven to be a highly effective tool in understanding the intrinsic geometry of a high-dimensional data set $\left\{x_i \right\}_{i=1}^{n} \subset \mathbb{R}^d$. The key ingredient is the construction of a Markov chain on the set, ... More
On the curvature of level sets of harmonic functionsJul 08 2013Jul 01 2014If a real harmonic function inside the open unit disk $B(0,1) \subset \mathbb{R}^2$ has its level set $\left\{x: u(x) = u(0)\right\}$ diffeomorphic to an interval, then we prove the sharp bound $\kappa \leq 8$ on the curvature of the level set $\left\{x: ... More
On Game-Theoretic Risk Management (Part One) - Towards a Theory of Games with Payoffs that are Probability-DistributionsJun 24 2015Sep 17 2015Optimal behavior in (competitive) situation is traditionally determined with the help of utility functions that measure the payoff of different actions. Given an ordering on the space of revenues (payoffs), the classical axiomatic approach of von Neumann ... More
Realizations of Seifert matrices by hyperbolic knotsApr 25 2007Recently Kearton showed that any Seifert matrix of a knot is S--equivalent to the Seifert matrix of a prime knot. We show in this note that such a matrix is in fact S--equivalent to the Seifert matrix of a hyperbolic knot. This result follows from reinterpreting ... More
Quantitative Constraint Logic Programming for Weighted Grammar ApplicationsMay 06 1997Constraint logic grammars provide a powerful formalism for expressing complex logical descriptions of natural language phenomena in exact terms. Describing some of these phenomena may, however, require some form of graded distinctions which are not provided ... More
On the Existence of Weak One-Way FunctionsSep 06 2016This note is an attempt to unconditionally prove the existence of weak one way functions (OWF). Starting from a provably intractable decision problem $L_D$ (whose existence is nonconstructively assured from the well-known discrete time-hierarchy theorem ... More
The affine inflation market modelsMar 17 2015Interest rate market models, like the LIBOR market model, have the advantage that the basic model quantities are directly observable in financial markets. Inflation market models extend this approach to inflation markets, where zero-coupon and year-on-year ... More
Analytic continuation of functional renormalization group equationsDec 19 2011Aug 17 2012Functional renormalization group equations are analytically continued from imaginary Matsubara frequencies to the real frequency axis. On the example of a scalar field with O(N) symmetry we discuss the analytic structure of the flowing action and show ... More
Critical Entropy of Quantum Heisenberg Magnets on Simple-Cubic LatticesDec 20 2009Mar 29 2010We analyze the temperature dependence of the entropy of the spin-1/2 Heisenberg model on the three-dimensional simple-cubic lattice, for both the case of antiferromagnetic and ferromagnetic nearest neighbor exchange interactions. Using optimized extended ... More
An epsilon-delta bound for plane algebraic curves and its use for certified homotopy continuation of systems of plane algebraic curvesMay 13 2015May 03 2016We explain how, given a plane algebraic curve $\mathcal{C}\colon f(x,y) = 0$, $x_1 \in \mathbb{C}$ not a singularity of $y$ w.r.t. $x$, and $\varepsilon > 0$, we can compute $\delta > 0$ such that $|y_j(x_1) - y_j(x_2)| < \varepsilon$ for all holomorphic ... More
Precision on the top massMay 04 2015In this talk I will focus on theoretical issues related to high precision determinations of the top mass. Several mass definitions are reviewed and their respective advantages and disadvantages are discussed. Precision determinations of the top mass will ... More
NNLO corrections to 2-jet observables in electron-positron annihilationJun 01 2006Jul 19 2006I report on a numerical program, which can be used to calculate any infra-red safe two-jet observable in electron-positron annihilation to next-to-next-to-leading order in the strong coupling constant alpha_s. The calculation is based on the subtraction ... More
Equivariant Dimensional RegularizationMar 17 1999Sep 28 1999The calculation of loop amplitudes with parity violation or spin effects within dimensional regularization needs a consistent definition of gamma5. Also loop calculations in supersymmetric theories need a consistent definition of gamma5. In this paper ... More
Event shapes and jet rates in electron-positron annihilation at NNLOApr 07 2009This article gives the perturbative NNLO results for the most commonly used event shape variables associated to three-jet events in electron-positron annihilation: Thrust, heavy jet mass, wide jet broadening, total jet broadening, C parameter and the ... More
Subtraction terms at NNLOFeb 20 2003Perturbative calculations at next-to-next-to-leading order for multi-particle final states require a method to cancel infrared singularities. I discuss the subtraction method at NNLO. As a concrete example I consider the leading-colour contributions to ... More
NLO Partonic Event GeneratorsMay 10 2002Merging the benefits of an NLO calculation with event generators is a topic of current interest. Among other things, it is advantageous to be able to generate unweighted events according to NLO matrix elements. I report on an algorithm which generates ... More
Fast evolution of parton distributionsMar 13 2002Jun 14 2002I report on a numerical program for the evolution of parton distributions. The program uses the Mellin-transform method with an optimized contour. Due to this optimized contour the program needs only a few evaluations of the integrand and is therefore ... More
The new Monte Carlo Event Generator Herwig++Aug 03 2004We present results obtained with the new Monte Carlo event generator Herwig++. In its first version (1.0), Herwig++ is capable of simulating e+e- Annihilation events. We compare results for different distributions with a vast amount of available data ... More
Implications of Running Neutrino Parameters for Leptogenesis and for Testing Model PredictionsSep 20 2004Oct 28 2004The running of neutrino parameters in see-saw models and its implications for leptogenesis and for testing predictions of mass models with future precision experiments are discussed using analytical approximations as well as numerical results.
Clustering Instabilities, Arching, and Anomalous Interaction Probabilities as Examples for Cooperative Phenomena in Dry Granular MediaOct 09 1998In a freely cooling granular material fluctuations in density and temperature cause position dependent energy loss. Due to strong local dissipation, pressure and energy drop rapidly and material moves from `hot' to `cold' regions, leading to even stronger ... More
Characterizations of metric trees and Gromov hyperbolic spacesMar 22 2006Aug 27 2007In a recent paper Chatterji and Niblo proved that a geodesic metric space is Gromov hyperbolic if and only if the intersection of any two closed balls has uniformly bounded eccentricity. In their paper, the authors raise the question whether a geodesic ... More
The Primordial Perturbation Spectrum and Large Scale StructureMar 01 1995Observational constraints on standard CDM spectra and perturbation spectra with broken scale invariance are discussed.
Search For Extra Dimensions At LEPOct 01 2004Searches for extra dimensions have been made at the four LEP experiments, ALEPH, DELPHI, L3 and OPAL, where different processes have been searched for within both the ADD and Randall-Sundrum scenarios. Since no signs of any signal have been observed the ... More
Locality in GNS Representations of Deformation QuantizationMar 09 1999In the framework of deformation quantization we apply the formal GNS construction to find representations of the deformed algebras in pre-Hilbert spaces over $\mathbb C[[\lambda]]$ and establish the notion of local operators in these pre-Hilbert spaces. ... More
Geometric Wave EquationsAug 23 2012In these lecture notes we discuss the solution theory of geometric wave equations as they arise in Lorentzian geometry: for a normally hyperbolic differential operator the existence and uniqueness properties of Green functions and Green operators is discussed ... More
Excited-state spectroscopy of triply-bottom baryons from lattice QCDFeb 06 2012May 23 2012The spectrum of baryons containing three b quarks is calculated in nonperturbative QCD, using the lattice regularization. The energies of ten excited bbb states with J^P = 1/2^+, 3/2^+, 5/2^+, 7/2^+, 1/2^-, and 3/2^- are determined with high precision. ... More
SU(3) chiral dynamics and baryon-baryon interactionsSep 21 2013Sep 24 2013We calculate hyperon-nucleon and hyperon-hyperon interactions at next-to-leading order in SU(3) baryon chiral perturbation theory extending earlier work by the Bonn-Juelich group. The constructed potentials in momentum space include all one- and two-meson ... More
Limits of PreprocessingApr 29 2011Aug 11 2011We present a first theoretical analysis of the power of polynomial-time preprocessing for important combinatorial problems from various areas in AI. We consider problems from Constraint Satisfaction, Global Constraints, Satisfiability, Nonmonotonic and ... More
Correlators, Feynman diagrams, and quantum no-hair in deSitter spacetimeOct 26 2010Dec 03 2010We provide a parametric representation for position-space Feynman integrals of a massive, self-interacting scalar field in deSitter spacetime, for an arbitrary graph. The expression is given as a multiple contour integral over a kernel whose structure ... More
Semiclassical wave functions and energy spectra in polygon billiardsAug 28 2014Dec 01 2014A consistent scheme of semiclassical quantization in polygon billiards by wave function formalism is presented. It is argued that it is in the spirit of the semiclassical wave function formalism to make necessary rationalization of respective quantities ... More
Simple applications of fundamental solution method in 1D quantum mechanics A talk given at the conference on: "Geometry Symmetry and Mechanics I" Lisbon, 11-16 July 2001Jul 04 2001A method of fundamental solutions has been used to show its effectiveness in solving some well known problems of 1D quantum mechanics (barrier penetrations, over-barrier reflections, resonance states), i.e. those in which we look for exponentially small ... More
Top Quark Mass and SupersymmetryJul 12 1994We summarize the expectations for the top quark mass in supersymmetric models and discuss the potential implications of its value measured by the CDF group in Fermilab.
The chirally rotated Schrödinger functional with Wilson fermions and automatic O(a) improvementAug 28 2010Feb 03 2011A modified formulation of the Schr\"odinger functional (SF) is proposed. In the continuum it is related to the standard SF by a non-singlet chiral field rotation and therefore referred to as the chirally rotated SF ($\chi$SF). On the lattice with Wilson ... More
On the Schroedinger functional in QCDDec 20 1993In a series of publications [\ref{LNWW},\ref{Schroedinger}], L\"uscher et al. have demonstrated the usefulness of the Schr\"odinger functional in pure SU(2) and SU(3) gauge theory. In this paper, it is shown how their formalism can be extended to include ... More
Semiclassical approximations for adiabatic slow-fast systemsMar 27 2012In this letter we give a systematic derivation and justification of the semiclassical model for the slow degrees of freedom in adiabatic slow-fast systems first found by Littlejohn and Flynn [5]. The classical Hamiltonian obtains a correction due to the ... More
Mass Corrections and Neutrino DISJul 10 2002Including the effects of the ${\cal{O}}(\gtrsim 1 {\rm GeV})$ masses of the charm quark, $\tau$ lepton and target nucleon in DIS phenomenology is discussed with applications to CC neutrino DIS: Neutrino data for $F_2$ are revisited within the global analysis ... More
Standard Model TheorySep 21 2015Recent progress in the field of precision calculations for Standard Model processes at the LHC is reviewed, highlighting examples of weak gauge-boson and Higgs-boson production, as discussed at the 27th Rencontres de Blois, 2015.
The renormalised quark mass in the Schrodinger functional of lattice QCD - a one-loop calculation with a non-vanishing background fieldNov 05 2002The critical quark mass, at which the renormalised mass vanishes, is computed in the Schrodinger functional scheme with a non vanishing background field at one-loop order of perturbation theory. Further one-loop calculations are done for the renormalisation ... More
An extension procedure for the constraint equationsSep 28 2016Let $( g, k)$ be a solution to the maximal constraint equations of general relativity on the unit ball $B_1$ of $\mathbb{R}^3$. We prove that if $(g,k)$ is sufficiently close to the initial data for Minkowski space, then there exists an asymptotically ... More
Well-Posedness and Stability for a Class of Stochastic Delay Differential Equations with Singular DriftAug 26 2016In this paper we prove well-posedness and stabibility of a class of stochastic delay differential equations with singular drift. Moreover, we show local well-posedness under localized assumptions.
Refined Heinz-Kato-Löwner inequalitiesAug 17 2016A version of the Cauchy-Schwarz inequality in operator theory is the following: for any two symmetric, positive definite matrices $A,B \in \mathbb{R}^{n \times n}$ and arbitrary $X \in \mathbb{R}^{n \times n}$ $$ \|AXB\| \leq \|A^2 X\|^{\frac{1}{2}} \|X ... More
On the Existence of Weak One-Way FunctionsSep 06 2016Oct 20 2016This note is an attempt to unconditionally prove the existence of weak one way functions (OWF). Starting from a provably intractable decision problem $L_D$ (whose existence is nonconstructively assured from the well-known discrete time-hierarchy theorem ... More
Time-inhomogeneous affine processes and affine market modelsDec 10 2015This thesis is devoted to the study of affine processes and their applications in financial mathematics. In the first part we consider the theory of time-inhomogeneous affine processes on general state spaces. We present a concise setup for time-inhomogeneous ... More
Heavy ion collisions and cosmologyDec 28 2015There are interesting parallels between the physics of heavy ion collisions and cosmology. Both systems are out-of-equilibrium and relativistic fluid dynamics plays an important role for their theoretical description. From a comparison one can draw interesting ... More
Variational principle for theories with dissipation from analytic continuationMar 23 2016May 13 2016The analytic continuation from the Euclidean domain to real space of the one-particle irreducible quantum effective action is discussed in the context of generalized local equilibrium states. Discontinuous terms associated with dissipative behavior are ... More
Generalized Kuga-Satake theory and good reduction properties of Galois representationsApr 20 2016In previous work we described when a single geometric representation, valued in a linear algebraic group, of the Galois group of a number field lifts through a central torus quotient to a geometric representation. In this paper we prove a much sharper ... More
α_S from LEPSep 03 2007Sep 19 2007Recent results on measurements of the strong coupling $\alpha_S$ from LEP are reported. These include analyses of the 4-jet rate using the Durham or Cambridge algorithm, of hadronic $Z^0$ decays with hard final state photon radiation, of scaling violations ... More