Related papers: One-Loop Electron Vertex in Yennie Gauge
Nonlinear Compton scattering is the process of emission of a single photon by a charge driven by an intense laser field. Here, we study the infrared behavior of the photon yield emitted via nonlinear Compton scattering. We first consider…
The scattering of two off-shell photons is an infrared-safe process in QCD. For photon virtualities in the range of a few GeV, accessible at LEPII, power-behaved contributions to the total cross section may become non-negligible. Based on a…
We obtain information on the QED photon amplitudes at high orders in perturbation theory starting from known results on the QED effective Lagrangian in a constant electric field. A closed-form all-order result for the weak field limit of…
Using the tip of a scanning probe microscope as a local electrostatic gate gives access to real space information on electrostatics as well as charge transport at the nanoscale, provided that the tip-induced electrostatic potential is well…
There has been growing interest in studying the behaviour of QED in its strong coupling limit. The reason for this is not only that it serves as a simple prototype gauge theory for testing nonperturbative calculational techniques which one…
A polynomial form is established for the off-shell CHY scattering equations proposed by Lam and Yao. Re-expressing this in terms of independent Mandelstam invariants provides a new expression for the polynomial scattering equations,…
The consistent construction of scattering amplitudes for processes with off-shell initial partons and involving electro-weak interactions is addressed.
We describe a general method for calculating the infra-red limit of physical quantities in unitary quantum field theories. Using analyticity of Green functions in a complex scale parameter, the infra-red limit is expressed as a contour…
We consider a one dimensional model of an electron in a doubly (or nearly) degenerate band that interacts with elastic distortions. We show that the electron equations of motion reduce to a set of coupled non-linear Schrodinger equations.…
We study theoretically the electronic properties of $c$-plane GaN/AlN quantum dots (QDs) with focus on their potential as sources of single polarized photons for future quantum communication systems. Within the framework of eight-band k.p…
In this paper we study the infra-red behaviour of a gauge invariant and physically motivated description of a charged particle in 2+1 dimensions. We show that both the mass shift and the wave function renormalisation are infra-red finite…
We present the ultraviolet poles and finite terms of two-loop vertex corrections for diagrams with massive partons in the eikonal approximation. We discover and prove that the results for a set of the corrections generalize to n-loop…
By introducing electron screening in the extended Koopmans' theorem we correctly describe the band gap opening in weakly as well as strongly correlated systems. We show this by applying our method to bulk LiH, Si, and paramagnetic as well…
A "natural" model for the QCD invariant (running) coupling, free of the IR singularity, is proposed. It is based upon the hypothesis of finite gluon mass $ m_{gl}$ existence and, technically, uses an accurate treating of threshold behavior…
We employ the harmonic superspace methods to study a six-dimensional $\mathcal{N}=(1,0)$ supersymmetric gauge theory with higher derivatives coupled to a hypermultiplet in the adjoint representation. By introducing a novel non-minimal…
We consider dressed 1-electron states in a translation-invariant model of non-relativistic QED. To start with a well-defined model, the interaction Hamiltonian is cutoff at very large photon energies (ultraviolet cutoff) and regularized at…
The canonical recursive Dyson--Schwinger equations for the three-gluon and ghost-gluon vertices are solved numerically. The employed truncation includes several previously neglected diagrams and includes back-coupling effects. We find an…
I consider an exact model of atomic spontaneous dipole emission and classical dipole radiation in a finite photonic band-gap structure. The full 3D or 2D problem is reduced to a finite 1D model, and then this is solved for analytically…
We uncover a method of calculation that proceeds at every step without fixing the gauge or specifying details of the regularisation scheme. Results are obtained by iterated use of integration by parts and gauge invariance identities.…
An exact formula is derived for the infrared singularities of dimensionally regularized scattering amplitudes in massless QCD with an arbitrary number of legs, valid at any number of loops. It is based on the conjecture that the…