A computational study of spin glasses and its spin coupling interactions

• Main Author: Wong, Yi Ren
• Other Authors: Chew Lock Yue
• Format: Final Year Project
• Language: English
• Published: 2018
• Subjects: DRNTU::Science::Physics::Atomic physics::Statistical physics
• Online Access: http://hdl.handle.net/10356/74188
• Institution: Nanyang Technological University

Spin Glasses are one of Physics’ most rich and complicated problems. It is a complex system with nontrivial low temperature behaviour, as a consequence of its random spin coupling interactions. The Spin Glass (SG) phase is characterized by the freezing of magnetic spins in random orientations below the critical temperature and can be observed across different SG models. These models may be differentiated from one another by the critical temperature and critical exponents measured or calculated from experiments and simulations which give rise to different universality classes in different regimes. We will explore in this thesis the critical phenomena of two separate new SG models − The Spin Glass Cellular Automata (SGCA) model and the Heterogeneous Spin Glass (HSG) model while reviewing other known SG models studied in literature. This thesis will first provide an introduction to the concept of complex systems and how spin glasses can be classified as one. Next, the Ising Model of Ferromagnetism will be introduced to provide a background on spin systems, criticality and finite size scaling. Subsequently, a brief introduction of spin glasses and literature on the Edward Anderson (EA), Sherrington-Kirkpatrick (SK) and Power Law SG models will be reviewed, and computational studies of these models on 1D spin glasses to replicate literature presented. Finally, the SGCA and HSG models will be defined and simulation results presented.