Strong-field subcycle control of dissociation dynamics via exceptional points of molecules in an electric field
Strong-field subcycle control of dissociation dynamics via exceptional points of molecules in an electric field
复制标题
通过电场中分子的异常点对解离动力学的强场子循环控制
DOI：
10.1103/physreva.95.063416
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
and T. Morishita
中科院分区：
文献类型：
--
作者：
C. Huang;O. I. Tolstikhin;and T. Morishita
取决于参数的量子系统可能在参数空间中具有异常点（EP），在这些点处，其共振态的复杂能量会合并。在这里，我们证明了静电场中分子的电子西格特态在核间距（场强平面）上具有 EP。考虑到分子正在经历解离（例如通过光电离），EP 使人们能够通过施加强低频激光脉冲来控制产物的最终状态。这种控制的可能性对脉冲强度具有阈值依赖性，脉冲强度是可观测量中 EP 的主要特征。控制发生在子周期时间尺度上，并且可以通过强场物理中使用的类型的少周期脉冲来完成。我们提出了一种预测和描述这种机制的理论，并通过该过程的计算来说明它。
Quantum systems depending on parameters may have exceptional points (EPs) in the parameter space where complex energies of their resonance states coalesce. Here we show that electronic Siegert states of molecules in a static electric field have EPs in the internuclear distance—field strength plane. Given a molecule undergoing dissociation launched, e.g., by its photoionization, the EPs enable one to control the final state of the products by applying a strong low-frequency laser pulse. The possibility of such a control has a threshold dependence on the pulse intensity, which is the main signature of the EPs in observables. The control occurs on subcycle time scales and can be accomplished by few-cycle pulses of the type used in strong-field physics. We present a theory predicting and describing this mechanism and illustrate it by calculations for the process.