Magnetic order in a quasicrystal

• Grant number: 23/01306-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2023
• End date: December 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Eric de Castro e Andrade
• Grantee: Glauco Fernandes da Silva Ramos
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 21/06629-4 - Electronic correlations in quantum materials: inhomogeneities and frustration, AP.JP2

Abstract

Motivated by the recent experimental realization of a heavy-fermion quasicrystal lattice, we would like to investigate the low-temperature behavior of localized spins living in a quasicrystal. Specifically, we will study the antiferromagnetic Ising model in the two-dimensional octagonal, or Ammann-Beenker, tiling. Previous studies show that this system displays long-range order in its ground state despite the lack of periodic order. We will consider two models. First, we will study the nearest-neighbor Ising model in this tilling. Then, we will consider diluted impurity Ising spins placed in a magnetic quasicrystal with their effective magnetic coupling mediated by the conduction electrons. We will focus on the ordered state at low temperatures in both scenarios.