Phase factors of periodically driven two-level systems

Abstract

Using a perturbative solution for a periodically driven two-level quantum system, we show how to obtain phase factors for both a two-level quantum system and two two-level quantum systems non-interacting and interacting. The method is easily implemented by numerical routines and presents the advantage of being stable for long-time periods. We furthermore explore the possibility of implementing a quantum phase gate using the perturbative solution.