标题： 空腔卡西米尔-波尔德力及其对基态化学反应性的影响 显示英文标题

标题： Cavity Casimir-Polder forces and their effects in ground state chemical reactivity

摘要： 在这里，我们对分子基态化学反应性在QED场景下如何被修改进行了基础研究，即当分子放置在腔体内且腔场与分子内的振动模式之间存在强耦合时的情况。 我们使用一个分子的模型系统（Shin-Metiu模型），其中核、电子和光子自由度被同等处理。 这个简化模型允许将精确的量子反应速率计算与基于腔体Born-Oppenheimer方法的过渡态理论预测进行比较。 我们证明了QED效应确实能够显著改变化学反应中的活化能垒，从而改变反应速率。 控制这一效应的关键物理参数是分子的永久偶极矩以及该量沿反应坐标的改变情况。 我们展示了有效耦合可以在实验上可实现的纳米颗粒-镜面腔中导致显著的单分子能量位移。 然后我们将经过验证的理论应用于一个实际案例（1,2-二氯乙烷分子中的内旋转），展示了反应如何根据分子偶极矩的分布被抑制或催化。 此外，我们讨论了这一过程中共振效应的缺失，这可以通过其与卡西米尔-波尔德力的联系来理解。 最后，我们处理了多分子强耦合的情况，并发现如果分子的永久偶极矩相对于腔场取向，则反应速率会发生集体修改。 这表明集体耦合也可以为耦合到腔模的分子集合的基态化学反应性提供一种修改机制。 显示英文摘要

摘要： Here we present a fundamental study on how the ground-state chemical reactivity of a molecule can be modified in a QED scenario, i.e., when it is placed inside a cavity and there is strong coupling between the cavity field and vibrational modes within the molecule. We work with a model system for the molecule (Shin-Metiu model) in which nuclear, electronic and photonic degrees of freedom are treated on the same footing. This simplified model allows the comparison of exact quantum reaction rate calculations with predictions emerging from transition state theory based on the cavity Born-Oppenheimer approach. We demonstrate that QED effects are indeed able to significantly modify activation barriers in chemical reactions and, as a consequence, reaction rates. The critical physical parameter controlling this effect is the permanent dipole of the molecule and how this magnitude changes along the reaction coordinate. We show that the effective coupling can lead to significant single-molecule energy shifts in an experimentally available nanoparticle-on-mirror cavity. We then apply the validated theory to a realistic case (internal rotation in the 1,2-dichloroethane molecule), showing how reactions can be inhibited or catalyzed depending on the profile of the molecular dipole. Furthermore, we discuss the absence of resonance effects in this process, which can be understood through its connection to Casimir-Polder forces. Finally, we treat the case of many-molecule strong coupling, and find collective modifications of reaction rates if the molecular permanent dipole moments are oriented with respected to the cavity field. This demonstrates that collective coupling can also provide a mechanism for modifying ground-state chemical reactivity of an ensemble of molecules coupled to a cavity mode.