scanning probe microscope with surface preparation for spectroscopy of quantum excitations

正在进行的电子元件的小型化已经达到了一个极限，量子物理和许多身体效应变得越来越重要。设备尺寸的缩小带来了奇异的电子效应，这些效应在飞秒到皮秒的时间尺度上和仅在几纳米尺度上的长度尺度上受到强烈波动的支配。一般来说，大多数材料的性质是由电子之间的相互作用强度和晶格振动决定的。然而，对这些现象中的大多数缺乏微观描述，需要新的高空间和时间分辨率的实验探测器。为了在微观水平上准确地研究这些相互作用，提出了一种新的扫描探针显微镜系统，该系统可以测量原子空间和皮秒时间分辨率的量子激发：量子激发显微镜。为此，扫描力显微镜将与具有超快电子和光学泵浦-探测能力的光学扫描近场显微镜相结合。利用这种新型仪器，可以在空间上分辨互补物理变量的随时间变化的涨落(其中包括电荷分布、磁有序、介电极化以及电子、光子和磁激发的能谱)。所有这些性质的综合表征都在同一表面上，这将使人们能够接触到以前没有在实验范围内的固体物理现象。量子激发显微镜将在空间上可视化关联电子系统中的金属-绝缘体相变及其特征涨落。此外，新仪器将允许有选择地操纵这些具有缺陷和掺杂原子的相变的动力学。一个主要目标是建立原子结构材料，并以高空间分辨率解决其中量子激发的超快动力学。超快扫描力显微镜和尖端增强拉曼光谱的结合使得可以在表面组装原子定义的结构，这些结构可以用作新的量子传感器。典型的传感器应用包括检测纳米磁场和电场以及微小的晶格扭曲，此外，能量分辨激发光谱和时间分辨泵浦-探测光谱的独特组合可以显示表面自旋或电荷激发的量子力学纠缠。纠缠态如何通过扩展的原子和分子网络传播，以及如何在这样的系统中抑制退相干等重要问题仍然没有答案，将在这项工作中得到解决。为此，将开发功能化表面，在其上可以存在长相干时间的自旋态和电荷态，并将使用原子操纵来创建可以容纳纠缠态的单独结构。

The ongoing miniaturization of electronic components has reached a limit where quantum physics and many body effects become increasingly important. Shrinking device dimensions brings exotic, electronic effects with it that are governed by strong fluctuations on femto- to picosecond time scales and on length scales of only a few nanometers. In general, most material properties are determined by the interaction strength of electrons with each other and with lattice vibrations. However, a microscopic description for most of these phenomena is lacking and new experimental probes with high spatial and temporal resolution are needed. In order to examine exactly these interactions on a microscopic level, a new scanning probe microscope system is proposed, one that can measure quantum excitations with atomic spatial and picosecond time resolution: quantum excitation microscope.To this end, a scanning force microscope and an optical scanning near field microscope with ultrafast electronic and optical pump-probe capabilities will be combined. With this novel instrument, time-dependent fluctuations of complementary physical variables can be spatially resolved (among them are charge distribution, magnetic ordering, dielectric polarization, as well as energy spectroscopy of electronic, photonic and magnetic excitations). The comprehensive characterization of these properties all on the same surface will allow access to phenomenon in solid state physics, that have not been within the experimental scope before.The quantum excitation microscope will the spatially resolved visualization of metal-insulator transitions and their characteristic fluctuations in correlated electron systems. In addition, the new instrument will allow selective manipulation of the dynamics of these phase transitions with defects and dopant atoms.A major goal is to build atomically structured materials and to resolve the ultra-fast dynamics of quantum excitations therein with high spatial resolution. The combination of ultra-fast scanning force microscopy with tip-enhanced Raman spectroscopy enables the assembly of atomically defined structures on surfaces that can be used as new quantum sensors. Prototypical sensor applications include the detection of nanoscopic magnetic and electric fields as well as small lattice distortions.Moreover, the unique combination of energy-resolved excitation spectroscopy and time-resolved pump-probe spectroscopy can demonstrate quantum mechanical entanglement of spin- or charge excitations on surfaces. The important questions of how entangled states propagate through extended atomic and molecular networks, and how decoherence could be suppressed in such systems are still unanswered and will be addressed in this work. To that end, functionalized surfaces on which spin- and charge states with long coherence times can exist will be developed, and atom manipulation will be used to create individual structures that can host entangled states.