3 papers
math-ph2020
Absence of eigenvalues in the continuous spectrum for Klein-Gordon operators
R. Ferreira, F. N. Lima, A. S. Ribeiro
We construct the one-dimensional analogous of von-Neumann Wigner potential to the relativistic Klein-Gordon operator, in which is defined taking asymptotic mathematical rules in or…
cond-mat.mes-hall2019
Spectra of electronic excitations in graphene near Coulomb impurities
A. I. Breev, R. Ferreira, D. M. Gitman +1
We study the problem of the electron excitation spectrum in the presence of point-like and regularized Coulomb impurities in gapped graphene. To this end, we use the Dirac model an…
hep-th2018
Role of switching-on and -off effects in the vacuum instability
T. C. Adorno, R. Ferreira, S. P. Gavrilov +1
We find exact differential mean numbers of fermions and bosons created from the vacuum due to a composite electric field of special configuration. This configuration imitates a fin…