Faculdade de Física

Nov 20, 2024 | epjc.epj.org | Faculdade de Física |Departamento de Física |Manuel E. Rodrigues |Diego Rubiera-Garcia

Eur. Phys. J.

Jul 29, 2024 | link.aps.org | Faculdade de Física |Departamento de Física |Manuel E. Rodrigues |Diego Rubiera-Garcia

In this paper, we investigate the gravitational lensing effect for the Schwarzschild-like black hole space-time in the background of a Kalb-Ramond (KR) field proposed by Yang et al. [Phys. Rev. D 108, 124004 (2023)]. The solution is characterized by a single extra parameter l, which is associated to the Lorentz symmetry breaking induced by the KR field. First, we calculate the exact deflection angle of massive and massless particles for finite distances using elliptic integrals.

Dec 5, 2023 | link.aps.org | Instituto de Física |Universidade Federal Fluminense |Faculdade de Física |Ramon Cardias

A spin Hamiltonian that characterizes interatomic interactions between spin moments is highly valuable in predicting and comprehending the magnetic properties of materials. Here, we explore a method for explicitly calculating interatomic exchange interactions in noncollinear configurations of magnetic materials considering only a bilinear spin Hamiltonian in a local scenario.

Aug 16, 2023 | onlinelibrary.wiley.com | Faculdade de Física

Multiple diffraction (MD) peaks exhibiting asymmetrical line profiles in azimuthal scans of weak Bragg reflections are direct evidence of dynamical diffraction within perfect crystalline domains (Renninger, 1937; Chang, 1984). As the profile asymmetries are related to the structure factor phases of two or more simultaneously excited hkl reflections, MD experiments have been used as a refinement tool capable of uncovering structural details beyond the resolution limit of other techniques.

May 18, 2023 | link.aps.org | Faculdade de Física

Abstract This study examines on-shell supersymmetry breaking in the Abelian N=1 Chern-Simons-matter model within a three-dimensional spacetime. The classical Lagrangian is scale invariant, but two-loop radiative corrections to the effective potential break this symmetry, along with gauge and on-shell supersymmetry. To investigate this issue, the renormalization group equation is used to calculate the two-loop effective potential.