论文标题
量子相干衍射成像
Quantum coherent diffractive imaging
论文作者
论文摘要
连贯的衍射成像使单个镜头中各个游离纳米颗粒的结构分析，并以前所未有的空间和时间分辨率来跟踪其光诱导的动力学。到目前为止，从CDI实验中从散射图像中检索结构信息的主要基于线性响应中经典散射的假设。对于强的激光场，尤其是对于共振激励，线性和经典描述都可能不再有效，因为人口耗竭和刺激的发射变得重要。在这里，我们开发了一个基于密度 - 矩阵的散射模型，以便在局部培养基响应中包括这种量子效应，并探索从线性到非线性CDI的过渡，以从氦纳米细胞中谐振散射。我们发现已经与实验可及的脉冲参数的线性响应案例显着不同，并表明非线性时空激发动力学在散射中导致了丰富的特征，从而导致量子相干衍射成像（QCDI）的建议是在强球XUV和X-Ray物理学中作为一个有希望的新型分支。
Coherent diffractive imaging has enabled the structural analysis of individual free nanoparticles in a single shot and offers the tracking of their light induced dynamics with unprecedented spatial and temporal resolution. The retrieval of structural information from scattering images in CDI experiments is so far mostly based on the assumption of classical scattering in linear response. For strong laser fields and in particular for resonant excitations, both the linear and the classical description may no longer be valid as population depletion and stimulated emission become important. Here we develop a density-matrix-based scattering model in order to include such quantum effects in the local medium response and explore the transition from linear to non-linear CDI for the resonant scattering from Helium nanodroplets. We find substantial departures from the linear response case already for experimentally reachable pulse parameters and show that non-linear spatio-temporal excitation dynamics results in rich features in the scattering, leading to the proposal of quantum coherent diffractive imaging (QCDI) as a promising novel branch in strong-field XUV and x-ray physics.
