We have studied the formation of ultracold RbSr molecules with laser pulses. After discussing the advantages of the Mott insulator phase for the control with pulses, we present two classes of strategies. The first class involves two electronic states. Two extensions of stimulated Raman adiabatic passage (STIRAP) for multilevel transitions are used: alternating STIRAP (A-STIRAP) and straddle STIRAP (S-STIRAP). Both transfer dynamics are modeled and compared. The second class of strategies involves only the electronic ground state and uses infrared (IR) and terahertz (THz) pulses. The molecular bond is first created by the application of a THz chirped pulse or $\pi$-pulse. Subsequently, the molecules are transferred to their rovibrational ground level using IR pulses. For this last step, different optimized pulse sequences that were obtained through optimal control techniques have been studied. The relative merits of these strategies in terms of efficiency and robustness are discussed with respect to the experimental feasibility based on present laser technologies.

中文翻译：

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超冷分子形成的激光控制：RbSr的情况

我们已经研究了利用激光脉冲形成超冷RbSr分子。在讨论了莫特绝缘子相在脉冲控制方面的优势之后，我们提出了两类策略。第一类涉及两个电子状态。使用刺激拉曼绝热通道（STIRAP）的两个扩展来进行多级转换：交替STIRAP（A-STIRAP）和跨骑式STIRAP（S-STIRAP）。两种传输动力学都进行了建模和比较。第二类策略仅涉及电子基态，并使用红外（IR）和太赫兹（THz）脉冲。首先通过施加THz rp脉冲或$\pi$-脉冲。随后，使用IR脉冲将分子转移到其振动基础水平。对于最后一步，已经研究了通过最佳控制技术获得的不同的最佳脉冲序列。在基于当前激光技术的实验可行性方面，讨论了这些策略在效率和鲁棒性方面的相对优点。