Preparing arbitrary mode superconducting LC entangled coherent state via a superconducting charge qubit

We design a pure solid-device comprised by LC circuits, which are coupled to superconducting charge qubit to entangle superconducting LC coherent modes. The operation time of the state of the system does not increase with the increase of the number of LC modes. Based on the measurement of charge states, an arbitrary mode of the state can be easily generated. A brief discussion about the experimental feasibility of the scheme is also shown. -- Highlights: → We design a pure solid-device to produce ECSs, the device is easy to be integrated and connected and the scheme can be easily extended to arbitrary-mode case. → Our system is robust to the perturbation of the voltage noise, the prepared ECSs are macroscopic and then more robust to environment than single-particle decoherence. → Once an ECS is experimentally realized, it is easier to build entanglement channels by emitting some of the entangled LC modes to receivers at a long distance since LC circuits are the building blocks of the information technology and all the essential techniques have already been well developed.