Banca de DEFESA: MARCONI SILVA SANTOS JUNIOR

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARCONI SILVA SANTOS JUNIOR
DATE: 05/04/2024
TIME: 09:00
LOCAL: Insitituto de Fìsica
TITLE:

Study of systems with electron-electron and electron-lattice interaction

KEY WORDS:

electron-electron, electron-lattice, localization 

PAGES: 100
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUBÁREA: Física da Matéria Condensada
SPECIALTY: Equação de Estado, Equilíbrio de Fases e Transições de Fase
SUMMARY:

In this work, we studied the electronic dynamics under the influence of Coulomb interaction

and also the effect of phonon interaction. Within the context of the Coulomb interaction,

we will demonstrate that the electron-electron term in a one-dimensional lattice creates

a subband of bounded states, initially standing out from the main band of states for

U = 8, also observed for U = 12. Our Hamiltonian considers the local and first-neighbor

interactions between electrons. The results show the appearance of a new subband due

to the interaction between the first neighbors and the broadening of this subband due to

the local interaction between the particles. The system’s dynamic under the action of an

external electric field shows that interaction between particles promotes coherent movement,

resulting in oscillation modes with doubled frequency. The electronic propagation under the

effect of electron-lattice interaction was investigated within the standard cubic nonlinear

profile. We introduce the coupling between the electron and the lattice through the hopping

distribution. We solve the coupled equation set to electron and lattice and calculate the

electronic position as a function of time. We provide a detailed investigation of the electron

and lattice dynamics for a wide range of electron-lattice coupling intensities. Our results

demonstrate that depending on the initial condition we consider and the intensity of the

electron-lattice interaction, we can obtain (or not) an electron-phonon pair formation.

Our results reveal that, depending on the initial velocity of the lattice and the degree

of electron-lattice the term, we can observe a repulsion between electron and lattice

deformation.

COMMITTEE MEMBERS:
Presidente - 2318874 - FRANCISCO ANACLETO BARROS FIDELIS DE MOURA
Interno(a) - 1366820 - IRAM MARCELO GLERIA
Interno(a) - 2580000 - VINICIUS MANZONI VIEIRA
Externo(a) à Instituição - ANDRE MAURICIO CONCEICAO DE SOUZA - UFS
Externo(a) à Instituição - Adauto José Ferreira de Souza - UFRPE