One experimental possibility of studying strongly correlated many-body systems, which typically arises in condensed matter physics, uses systems of cold atoms trapped in a periodic potential formed from standing waves of laser light, an optical lattice. In the field of cold atoms, a major ambition is to observe sensitive many-body phenomena beginning with quantum magnetism. In this thesis, many-body dynamics in optical lattices for different spin models is studied.The interest of this work focusses on analysing interesting methods for state preparationin quantum magnetism. One way of controlling the dynamics in optical lattices is by using a diabatic state preparation, where we can access states that are diffcult to prepare by approaching them via more easily prepared states, based around parameters of current experiments. However,by manipulating the interactions, or by other alternative methods, magnetic state preparation might be also accessible. These techniques are explored more in detail, looking at the magnetically ordered quantum states that can be realised. This study is primarily numerical, using Exact Diagonalisation for small system sizes, and Density Matrix Renormalization group methods (t-DMRG), like the Time Evolving Block Decimation (TEBD) algorithm, to study the time-dependent dynamics in one-dimensional lattice systems for bigger systems, by making use of the Matrix Product States (MPS) representation. These studies have implications for on-going experiments and open up a new way to study quantum magnetism in systems of cold atoms in optical lattices.
|Date of Award||5 Jul 2016|
- University Of Strathclyde
|Sponsors||Air Force Office of Scientific Research AFOSR (the) & University of Strathclyde|