Invariants-based shortcuts for fast generating Greenberger—Horne—Zeilinger state among three superconducting qubits

As one of the most promising candidates for implementing quantum computers, superconducting qubits (SQs) are adopted for fast generating the Greenberger-Horne-Zeilinger (GHZ) state by using invariants-based shortcuts. Three SQs are separated and connected by two coplanar waveguide resonators (CPWRs) capacitively. The complicated system is skillfully simplified to a three-state system, and a GHZ state among three SQs is fast generated with a very high fidelity and simple driving pulses. Numerical simulations indicate the scheme is insensitive to parameter deviations. Besides, the robustness of the scheme against decoherence is discussed in detail.