Quantum Orders and Collective degrees offreedom in Many-body systems

Rishabh Khare, Supervisor Dr. Siddhartha Lal

Published May 1, 2016• 0 citations

Abstract

The anti-ferromagnetic Lieb-Mattis model is investigated in detail. Symmetry breaking, low-lying excitation spectrum and macroscopic quantity like Berry phase are calculated for this model. Superconductivity is studied with respect to the collective modes of negative U Hubbard model and the BCS superconductor. The Integer Quantum Hall is looked into by various ways such as by using the center of mass and orbital center coordinates. The importance of domain wall in a Quantum Hall system is stressed.These systems are particularly chosen as they are prototypical/ archetypal fermionic and spin quantum condensed matter systems. iii

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