论文标题
由单周期terahertz脉冲引起的定向量子复兴
Orientational quantum revivals induced by a single-cycle terahertz pulse
论文作者
论文摘要
在几个量子系统中观察到了由波包的自我干扰引起的量子复兴现象，并在光谱应用中广泛使用。在这里，我们介绍了专门使用单周期THZ脉冲的方向量子复兴（OQR）的结合分析和数值研究。作为原理的证明，我们使用实验可访问的脉冲参数检查了线性极性分子HCN中的方案，并获得无场的OQR，而无需突然影响限制的条件。为了可视化所涉及的量子机制，我们使用时间进化运算符的Magnus扩展得出了三态模型。有趣的是，THZ脉冲与电偶极矩的相互作用可以激活直接多光子的过程，从而导致OQR增强功能超出了旋转阶梯式攀爬机制，从旋转基态造成的增强功能。这项工作为分子旋转的量子控制提供了一种明确且可行的方法，这是当前研究工作的核心，具有原子和分子物理学，光化学和量子信息科学的潜在应用。
The phenomenon of quantum revivals resulting from the self-interference of wave packets has been observed in several quantum systems and utilized widely in spectroscopic applications. Here, we present a combined analytical and numerical study on the generation of orientational quantum revivals (OQRs) exclusively using a single-cycle THz pulse. As a proof of principle, we examine the scheme in the linear polar molecule HCN with experimentally accessible pulse parameters and obtain strong field-free OQR without requiring the condition of the sudden-impact limit. To visualize the involved quantum mechanism, we derive a three-state model using the Magnus expansion of the time-evolution operator. Interestingly, the THz pulse interaction with the electric-dipole moment can activate direct multiphoton processes, leading to OQR enhancements beyond that induced by a rotational ladder-climbing mechanism from the rotational ground state. This work provides an explicit and feasible approach toward quantum control of molecular rotation, which is at the core of current research endeavors with potential applications in atomic and molecular physics, photochemistry, and quantum information science.
