The quantum level population behavior of two coupled flux qubits depending on the external driving field characteristics is studied. Explicit expressions for the multiphoton transition probabilities at an arbitrary control field amplitude are obtained for the case of small tunnel splitting energies. We describe the controllable features of their formation and thereby the creation or destruction of entanglement on the direct interlevel transition and during the transition through intermediate states by system bias tuning. We found a feature of the qubit population inversion that results in the independence of the resonance positions from the qubit coupling strength. Using the Floquet-Markov equation, we numerically demonstrate that the positions of multiphoton resonances are stable to dissipative processes.

中文翻译：

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通过驱动场控制两个耦合量子位中多光子跃迁的光谱特征

研究了取决于外部驱动场特性的两个耦合通量量子位的量子级布居行为。对于小隧道分裂能量的情况，获得了任意控制场幅度下的多光子跃迁概率的显式表达式。我们描述了它们形成的可控特征，从而通过系统偏置调整在直接层间跃迁和通过中间态的跃迁过程中产生或破坏纠缠。我们发现了量子比特群体反转的一个特征，它导致共振位置与量子比特耦合强度无关。使用 Floquet-Markov 方程，我们从数值上证明了多光子共振的位置对于耗散过程是稳定的。