Quantum coherence in a superconducting circuit coupled with a dissipative cavity field

Abstract

Quantum coherence represents a basic feature of a quantum system that is not present in the classical world. Here, we explore the dynamic behaviors of quantum coherence in two charge qubits who are strongly coupled with a single-mode dissipative cavity field. The results show that quantum coherence is sensitive to the coupled system parameters including qubit dissipation rate, initial qubit distribution angle, and coherent state intensity of the cavity field. Additionally, during the dynamic evolution, quantum coherence behaves periodically in the case of the qubit distribution angle, and this periodicity depends on the qubit dissipation rate. Also, the increasing coherent state intensity of cavity field can enhance the magnitude of quantum coherence, meaning that coherence resource in dissipative solid state quantum system can be controlled to some extent. This controllable coherence resource in engineering applications may quantify the advantage enabled in the superconducting circuit for processing the remarkable quantum information tasks.