Superconducting qubit network: Physics and applications.

In the present time, there is growing interest in superconducting qubit networks (SQNs) ---solid-state systems demonstrating the coherent collective quantum-mechanical dynamics on a macroscopic scale. SQNs appear to be unique systems in which various important factors for potential applications, such as low dissipation and decoherence, electromagnetic field tunable qubit parameters, strong electromagnetic coupling between qubits and a well established measurement setup can be combined. Embedding superconducting qubits in a low dissipative resonator results in a strong coupling between single qubits and cavity photons, which has allowed to observe an entanglement between qubits states. SQNs based on both flux qubits and transmon qubits permit to manipulate quantum states of single qubits at long coherence time and allow the experimental observation of stable collective quantum states. Recently, we propose a novel approach to detect single microwave photons based on a coherent collective oquantum states occurring in SQNs embedded in a low-dissipative superconducting resonator. SQNs are also most promising systems for the implementation of analog quantum simulation.