Banca de DEFESA: PAULO HENRIQUE GONÇALVES MORAES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE: PAULO HENRIQUE GONÇALVES MORAES
DATA: 29/08/2025
HORA: 10:00
LOCAL: Remota (On-line)
TÍTULO: Estudo do emaranhamento e transições de fase quânticas em cadeias do modelo ANNNI com campo transverso
PALAVRAS-CHAVES: Entropia de von Neumann; Modelo ANNNI com campo transverso; Transições de fase quânticas.
PÁGINAS: 58
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

In this work, quantum phase transitions in the one-dimensional Axial
Next-Nearest Neighbor Ising (ANNNI) model with transverse field were
investigated, with emphasis on the role of bipartite entanglement as a critical
indicator. The sensitivity of von Neumann entropy to phase changes was
analyzed, and how different choices of bipartitions influence its response in the
transition was evaluated.
Due to the absence of an exact solution for the model with transverse field at
the thermodynamic limit, we applied the Lanczos method to numerically
determine the ground state of finite chains with periodic boundary conditions.
The quantum critical points were estimated using finite-size scaling (FSS)
techniques. In addition, spin correlation functions and the structure factor were
calculated, allowing us to identify magnetic ordering and frustration effects,
including patterns associated with the devil's staircase. The results reinforce
that von Neumann entropy, in addition to adequately identifying the transition
between commensurate phases, is sensitive to spatial modulations originating
from the competition between interactions in the model.

MEMBROS DA BANCA:
Externo ao Programa - 389.***.***-20 - ANDRÉ DE PINHO VIEIRA - USP
Interno - 1548848 - EDUARDO COSTA GIRAO
Interno - 1446938 - FRANCISCO WELINGTON DE SOUSA LIMA
Presidente - 423297 - JOSE PIMENTEL DE LIMA
Externo ao Programa - 344.***.***-20 - RAIMUNDO ROCHA DOS SANTOS - UFRJ