对存在循环相互作用的自旋梯耦合的两粒子的量子失协进行了讨论。对于双边耦合的情况,两耦合粒子的量子失协都是时间的周期函数,但是与时间间隔无关。通过讨论我们发现量子失协比量子纠缠更有利于量子信息的处理和量子计算。
The quantum discord of two qubits coupled to a spin ladder with cyclic interaction is investigated. For bilateral coupling, both discords of two-coupled qubits are periodic function of time but irrelevant to time interval. It is shown that quantum discord is more valid than quantum entanglement for quantum correlation in spin ladder system.