Sudden change of the geometric quantum discord and quantum coherence in dissipative superconducting circuit systems with the time-dependent electromagnetic field

Abstract

We investigate the influence of a time-dependent electromagnetic field(TDEF) on the double sudden change of the 1-norm geometric quantum discord(GQD) and sudden change of quantum coherence for superconducting circuit systems under spontaneous emission, where two supercon ducting qubits are each coupled to their own LC circuit or uniformly coupled to a common LC circuit, respectively. It is shown that the double sudden change of the GQD can be controlled, and the frozen time during which the GQD keeps nearly constant can be lengthened by applying the TDEF. Furthermore, we also find that the TDEF can delay the “critical point” of sudden change for quantum coherence and slow down the decay of quantum coherence. Finally, we explore how the TDEF affects the superconducting circuits system’s information flow by using trace distance and the optimal control scheme is sought by comparing the two coupled mode.