手征态间存在隧穿效应时手性混合物的光泵浦对映转化
Optical-pumping enantio-conversion of chiral mixtures in presence of tunneling between chiral states
AI总结：
该研究针对手征态间隧穿不可忽略的手性分子，提出基于四能级模型的光泵浦对映转化方案，通过绝热消除与参数设计实现手征态选择性激发，结合系统耗散达成高效对映转化。
摘要：
手性混合物的对映转化，即将由左旋和右旋手性分子组成的混合物转化为纯手性系综，已成为化学与生物领域的重要研究课题。在以往的对映转化研究中，左旋与右旋手征态之间的隧穿相互作用常被忽略。然而对于某些手性分子而言，这种隧穿相互作用十分显著，不可忽视。本文基于包含两个手征基态、两个非手征激发态且手征态间存在隧穿相互作用的手性分子四能级模型，提出了一种通过光泵浦实现手性混合物对映转化的方案。在单光子大失谐与双光子共振条件下，其中一个非手征激发态被绝热消除。通过合理设计电磁场的失谐量与耦合强度，可消除两个手征态之间的隧穿相互作用，以及其中一个手征态与剩余非手征激发态之间的相互作用。由此，一个手征态保持不变，而另一个可被激发至非手征激发态，从而实现手征态选择性激发。通过数值计算两个手征基态的布居数与对映体过量值，我们观察到在系统耗散与手征态选择性激发的共同作用下，可实现高效的对映转化。
英文摘要：
Enantio-conversion of chiral mixtures, converting the mixtures composed of left- and right-handed chiral molecules into the homochiral ensembles, has become an important research topic in chemical and biological fields. In previous studies on enantio-conversion, the tunneling interaction between the left- and right-handed chiral states was often neglected. However, for certain chiral molecules, this tunneling interaction is significant and cannot be ignored. Here we propose a scheme for enantio-conversion of chiral mixtures through optical pumping based on a four-level model of chiral molecules, comprising two chiral ground states and two achiral excited states, with a tunneling interaction between the chiral states. Under one-photon large detuning and two-photon resonance conditions, one of the achiral excited states is eliminated adiabatically. By well designing the detuning and coupling strengths of the electromagnetic fields, the tunneling interaction between two chiral states and the interaction between one of the chiral states and the remaining achiral excited state can be eliminated. Consequently, one chiral state remains unchanged, while the other can be excited to an achiral excited state, establishing chiral-state-selective excitations. By numerically calculating the populations of two chiral ground states and the enantiomeric excess, we observe that high-efficiency enantio-conversion is achieved under the combined effects of system dissipation and chiral-state-selective excitations.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
