Hamiltonian encoding-observable decoding methods for open quantum systems: Application to a single-qubit system

Control mechanism is usually much more complex for open quantum systems than closed systems. In this article, the Hamiltonian encoding-observable decoding method for open quantum systems is formulated, starting from the Lindblad equation. The dipole-field-induced and dissipation-induced quantum pathways in Liouville space are analyzed with this method for a single-qubit open system. Different signatures can be found in the decoding results, and the amplitudes of dipole-field-induced quantum pathways change with the control field while those of dissipation-induced quantum pathways are constant. Analysis with this method should be helpful to understand the control mechanism for open quantum systems.