OPEN QUANTUM SYSTEMS AND ITS APPLICATIONS

Abstract

In this thesis, we will investigate various aspects of open quantum systems, i.e. systems that are interacting with an external environment. We will first study how the phenomenon of entanglement between two qubits and spin squeezing of a large spin system can be optimised by the environment, and find that contrary to conventional wisdom, the environment may sometimes assist with the formation of these quantum effects. We will then turn our attention to driven systems, whereby we first investigate the effects of dissipation and dephasing on population transfer between energy levels as a result of adiabatic driving. We will then extend these results to investigate the effects of dissipation on adiabatic quantum pumping.