(color online) (a) Schematic diagram to transfer a quantum state from the left unit to the right unit. The quantum state initially encoded on the left unit is transferred to the right unit, the state can be transferred completely by using adjustable OC leakage rates . A black body absorber can ensure the state transfers in a single direction. (b) Schematic diagram of each unit. The SQ is coupled with the SR by capacitively coupling. The SR and the OC are coupled to the NAMR respectively. The coupling between SQ and SR is driven by a microwave field, meanwhile the SR is driven by a coherent classical field on the microwave band and the OC is driven by an optical field.