Efeitos de curvatura em sistemas bidimensionais de matéria condensada

Abstract

The influence of curved background on the properties of Condensed Matter systems is a significant question for a broad class of physical applications, catching the curiosity because of their interesting features in a rich interface between many research areas. In this thesis, we introduce an analytically solvable model of Dirac fermions with imaginary mass on the sphere. We show the existence of an in nite sequence of exceptional points (EP), which depend on the radius (curvature) of the sphere. We employ quench dynamics to characterize curvaturedependent Non-Hermitian phase transitions. We demonstrate that the existence of singular points of the Loschmidt echo and the fidelity are an unambiguous signature of geometric EPs that distinguish between different phases of the model. Also, we use numerical techniques to solve the Bose-Hubbard hamiltonian that simulates the hyperbolic geometry. In this system, we attempt to verify whether we can observe a bound-states comprising a pair of atoms in the presence of repulsive interactions in a hyperbolic lattice. This system is a playground to simulate a space with negative curvature, that is difficult to simulate in a euclidean space without distortions.