Study on Disordered and Dissipative Quantum Spin Systems
Disorders and dissipations play the key role in the understanding of quantum coherent system. In this thesis, I'm using numeric method plus theoretical analysis to answer the questions: What are the low energy modes in disordered quantum spin system? How will environment dissipation damp the spin system's quasi-particle excitation quantitatively?
There are three parts in my thesis. Part 1 is the study of disordered quantum Ising chain. Part 2 is a numerical method for analytic continuation. Part 3 is the study of dissipative quantum Ising chain.