Approximate bang-bang Lyapunov control for closed quantum systems

This paper proposes a new approximate bang-bang Lyapunov control that can achieve rapid state control for quantum systems. A construction method is presented to design the degrees of freedom in the Lyapunov function so that the control law can guarantee the convergence of the system to a target eigenstate being isolated in the invariant set. Simulation experiments on a three-level system demonstrate that the proposed method can achieve good performance for rapid state control of quantum systems.