Pole Placement Approach to Coherent Passive Reservoir Engineering for Storing Quantum Information
For quantum information storage, this provides a constructive feedback design methodology to engineer decoherence-free subsystems, addressing a key challenge in quantum control.
The paper proposes a pole placement approach for coherent passive reservoir engineering to synthesize decoherence-free subsystems (DFS) for storing quantum information, overcoming limitations of open-loop methods. The method enables DFS creation from components lacking such modes via coherent quantum feedback control.
Reservoir engineering is the term used in quantum control and information technologies to describe manipulating the environment within which an open quantum system operates. Reservoir engineering is essential in applications where storing quantum information is required. From the control theory perspective, a quantum system is capable of storing quantum information if it possesses a so-called decoherence free subsystem (DFS). This paper explores pole placement techniques to facilitate synthesis of decoherence free subsystems via coherent quantum feedback control. We discuss limitations of the conventional `open loop' approach and propose a constructive feedback design methodology for decoherence free subsystem engineering. It captures a quite general dynamic coherent feedback structure which allows systems with decoherence free modes to be synthesized from components which do not have such modes.