Dynamical processes in ultralong-range Rydberg molecules

超长程里德堡分子（ULRM）是一种具有新型化学键合机制的外来分子。它们在2000年由格林、Sadeghpour和Dickinson在理论上预测，并在2008年由Pfau等人利用光缔合光谱首次在实验上发现。自那时以来，超冷原子物理已经成为与量子光学、量子多体物理和超冷原子物理密切相关的一个独立的研究领域。ULRM由里德堡原子和基态原子组成的不同束缚态混合物，具有巨大的键长和偶极矩，并继承了对外场的敏感性。虽然对双原子和多原子超晶格结构的研究已经展示了丰富的唯象学和通过场设计束缚分子量子态的可能性，但对量子动力学过程，或者换句话说，Rydberg超晶格化学，却知之甚少。这项建议旨在通过开发一个系统的方法来缩小这一差距，以潜在的弹性和非弹性过程发生的ULRM。因此，这将为这些新的分子物种的表征及其Rydberg化学反应动力学提供一个重要的飞跃，具体来说，我们将探索从ULRM的广泛的电子结构计算中获得的单个和多个绝热势能面上的波包动力学。泵探测技术将采用和模拟准备和探测的初始和最终的时间波包。在单个表面上，量子动力学是绝热电子特性，我们感兴趣的是多个干涉和散射事件可能分散，离域和破碎的原始振动波包。在几个势能面在坐标空间中局部相互作用的情况下，我们将探讨通过避免交叉或圆锥交叉的超快非辐射衰变过程的可能性.由于里德伯电子的自旋和基态原子的电子和核自旋的自旋相互作用效应，以及里德伯电子和与基态原子的相互作用的自旋-轨道相互作用效应都应包括在内。本课程将研究各种不同的弹性和非弹性Rydberg化学过程，包括自旋变化碰撞、缔合电离和重Rydberg态的形成，以及特别是复合和解离过程。外场将被用来控制分子的几何形状和控制相应的动力学。所采用的波包传播方法将基于位置空间中的多维网格，通过离散变量表示和分子多模式振动动力学的多配置时间相关哈特里方法。

Ultralong-range Rydberg molecules (ULRM) represent an exoticmolecular species with a novel chemical binding mechanism. Theyhave been predicted theoretically in 2000 by Greene, Sadeghpourand Dickinson and were firstly found experimentally in 2008 by Pfauet al employing photoassociation spectroscopy. Since then ULRMhave become an independent research area closely interacting withquantum optics, quantum many-body physics and ultracold atomicphysics. Consisting of a disparate bound state mixture of Rydbergand ground state atoms ULRM exhibit huge bond lengths and dipolemoments and inherit the sensitivity to external fields. Whileinvestigations on the structure of diatomic and polyatomic ULRM havebeen demonstrating the enormously rich phenomenology and thepossibility to design bound molecular quantum states via fields, verylittle is known about quantum dynamical processes, or, in other words,Rydberg ULRM chemistry. This proposal aims at closing this gap bydeveloping a systematic approach to the underlying elastic andinelastic processes taking place for ULRM. It will, as such, provide amajor leap forward with respect to the characterization of these novelmolecular species and their Rydberg chemical reaction dynamics.Specifically we will explore the wave packet dynamics on single andmultiple adiabatic potential energy surfaces which we obtain fromextensive electronic structure calculations of ULRM. Pump-probetechniques will be employed and emulated to prepare and probe theinitial and final time wave packet. On a single surface the quantumdynamics is adiabatic electronic character and we are interested inthe multiple interference and scattering events possibly dispersing,delocalizing and fragmenting the original vibrational wave packet. Inthe case of several potential energy surfaces which interact locally incoordinate space we will probe the possibility of ultrafast nonradiativedecay processes through either avoided crossings or conicalintersections. Spin interaction effects due to the spin of the Rydbergelectron and the electronic and nuclear spin of the ground stateatoms, as well as spin-orbit interaction effects for both the Rydberg electron and the interaction with the ground state atoms shall beincluded. A variety of different elastic and inelastic Rydberg chemicalprocesses will be investigated, including spin changing collisions,associative ionization and heavy Rydberg state formation as well as inparticular recombination and dissociation processes. External fieldswill be used to control the geometry of the molecules and to steer thecorresponding dynamics. The employed wave packet Propagation methods will be based on multi-dimensional grids in position spacevia discrete variable representations and the Multi-ConfigurationTime-Dependent Hartree approach for multi-mode vibrationaldynamics of molecules.