论文标题
增强两个振荡器之间的量子交换
Enhancing quantum exchanges between two oscillators
论文作者
论文摘要
我们探讨了两个量子振荡器可以通过三级系统有效地交换其量子状态的程度，该系统可以是固体中有色中心的自旋水平。使用汉密尔顿工程和量子控制技术获得了高过渡概率。从弱耦合近似开始，我们在自旋振荡器相互作用的哈密顿量中得出条件，从而实现了量子的高保真交换。我们发现，对于任意旋转振荡器耦合，无法满足这些条件。为了克服这一限制，我们说明了应用于三级系统的时间依赖性控制场如何导致有效的动态，从而执行所需的激发交换。在（超）强耦合方向上，激发将激发的分散在许多振荡器状态下引起了重要的保真度。我们表明，通过合适的控制场可以大大降低这种有害效应，这些控制场是使用最佳控制数值算法计算的。
We explore the extent to which two quantum oscillators can exchange their quantum states efficiently through a three-level system which can be spin levels of colored centers in solids. High transition probabilities are obtained using Hamiltonian engineering and quantum control techniques. Starting from a weak coupling approximation, we derive conditions on the spin-oscillator interaction Hamiltonian that enable a high-fidelity exchange of quanta. We find that these conditions cannot be fulfilled for arbitrary spin-oscillator coupling. To overcome this limitation, we illustrate how a time-dependent control field applied to the three-level system can lead to an effective dynamic that performs the desired exchange of excitation. In the (ultra) strong coupling regime, an important loss of fidelity is induced by the dispersion of the excitation onto many Fock states of the oscillators. We show that this detrimental effect can be substantially reduced by suitable control fields, which are computed with optimal control numerical algorithms.
