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

► 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.