Related papers: Positron potential and wavefunction in LaFeAsO
The analysis using the partial-wave series expansion (PWSE) method in spherical coordinates is extended to evaluate the acoustic radiation force experienced by rigid oblate and prolate spheroids centered on the axis of wave propagation of…
In this paper we discuss the magnetic Purcell effect of a magnetic dipole near a semi-infinite antiferromagnet. Contrary to the electric Purcell effect, the magnetic one is not so well studied in the literature. We derive the dispersion…
The s manifold energy levels for phosphorus donors in silicon are important input parameters for the design and modelling of electronic devices on the nanoscale. In this paper we calculate these energy levels from first principles using…
We measured the Raman and the Infrared phonon spectrum of SmFeAsO polycrystalline samples. We also performed Density Functional Theory calculations within the pseudopotential approximation to obtain the structural and dynamical lattice…
Biased conducting-tip atomic force microscopy (AFM) has been shown to write and erase nanoscale metallic lines at the LaAlO3/SrTiO3 interface. Using various AFM modes, we show the mechanism of conductivity switching is the writing of…
The electron-phonon coupling of LaO$_{1-x}$F$_x$FeAs is re-investigated on the basis of density functional theory in local density approximation. The implications of the $(\pi,\pi)$ nesting of the Fermi surfaces are carefully studied and…
In our previous work [Phys. Rev. D 101 (2020) 075046], we have proposed to install FAr Detectors at the Electron Positron Collider (FADEPC) to enhance the discovery potential of long-lived particles (LLPs). In this study, we consider eight…
We introduce a scalable, translationally invariant variational theory for ab initio polarons that remains applicable across coupling regimes without resorting to supercells. Our approach combines a momentum-projected Toyozawa-type…
The positron-electron annihilation gamma-ray spectra of linear alkanes CnH2n+2 (n=1-12) have been studied systematically. A profile quality (PQ) parameter, is introduced to assess the agreement between the obtained theoretical profiles and…
We have performed the numerical modeling of Ge(111)-(2x1) surface electronic properties in vicinity of P donor impurity atom located near the surface. We have found a notable increase of surface $LDOS$ around surface dopant near the bottom…
Positron and electron cosmic rays provide a complementary way to study the galactic environment. The actual cosmic rays experiments, for instance PAMELA and HEAT, have presented very exciting results in this field. The observed positron…
We consider the properties of a single impurity immersed in a Fermi sea close to an interspecies p-wave Feshbach resonance. We calculate its dispersion and spectral response to a radiofrequency pulse. In the presence of a magnetic field,…
In this work, we study underlay radar-massive MIMO cellular coexistence in LoS/near-LoS channels, where both systems have 3D beamforming capabilities. Using mathematical tools from stochastic geometry, we derive an upper bound on the…
The effect of confinement on the self-annihilation rate of positronium is studied in three levels of approximation. Artificial restriction of the electron-positron separation leads to an increase in the annihilation rate over its vacuum…
Quantum Monte Carlo calculations of the relaxation energy, pair-correlation function, and annihilating-pair momentum density are presented for a positron immersed in a homogeneous electron gas. We find smaller relaxation energies and…
Positron scattering and annihilation on noble gas atoms below the positronium formation threshold is studied ab initio using many-body theory methods. The many-body theory provides a near-complete understanding of the…
The comparative study of structural, electronic properties, topology of the Fermi surface, and the features of chemical bonding in layered 1111-oxyarsenides LaRhAsO and LaIrAsO has been performed based on the results of ab initio modeling…
We measured the electronic structure of an iron arsenic parent compound LaFeAsO using angle resolved photoemission spectroscopy (ARPES). By comparing with a full-potential Linear Augmented PlaneWave calculation we show that the extra large…
The inclusive cross-section of annihilation in flight $e^+e^-\rightarrow\gamma\gamma$ of 430 MeV positrons with atomic electrons of a thin diamond target has been measured with the PADME detector at the Laboratori Nazionali di Frascati. The…
The AMS-02 collaboration has recently released data on the positron fraction $e^+/(e^-+e^+)$ up to energies of about 350 GeV. If one insists on interpreting the observed excess as a dark matter signal, then we find it is best described by a…