Low-temperature near-field microscope (LT-SNOM)

应用于低温近场显微镜，可以在10到300开尔文的温度范围内记录太赫兹、红外和光学频率范围的近场光谱，横向分辨率在10到50 nm之间。这一分辨率大大低于衍射极限，从而实现了前所未有的实验进展。为此，除主仪器外，还应用了太赫兹光谱分析系统、二氧化碳激光光源以及红外光谱仪。对于红外光谱，我们还需要一个红外宽带光源，可以在我们正在申请的室温近场显微镜上并行使用。这一文书的资助可能性是在魏茨教授召集哥廷根教授的基本资助框架内批准的，是建立该小组的重要工具。有了显微镜，我们将能够在现代固态研究领域进行各种高度创新的实验。例如，我们将能够在有机电子领域进行独特的调查。具体地说，我们将首先能够以纳米分辨率局部可视化单个聚合物纤维和低分子薄膜的太赫兹电导率的温度依赖关系。这将大大加深对电荷传输机制理论的理解。此外，我们将利用本地红外光谱的独特能力来检测有机半导体的电退化随温度的变化。利用已建立的方法，我们还将增加对新型金属有机骨架的导电性的基本理解。对于范德华材料领域，所应用的仪器将是极其重要的，因为它将允许对例如新的超导相的独特理解。为此，我们将使用横向分辨率低于10 nm的红外局部电导率随温度变化的横向映射来潜在地首先检测局部超导相的出现，例如在菱面体多层石墨烯中。此外，我们将首先能够跟踪双层石墨烯或由新型二维聚合物和石墨烯组成的异质结构中拓扑保护态的温度依赖性。这一独特的仪器还将允许对强关联氧化物和电荷密度材料中随温度变化的相变的局部现象进行独特的洞察。

The applied for low-temperature near-field microscope allows to record near-field optical spectra in the range of THz, infrared and optical frequencies in the temperature regime between 10 and 300 Kelvin with a lateral resolution between 10 and 50 nm. This resolution is significantly below the diffraction limit, and thus allows unprecedented experimental progress. To this end additionally to the main instrument, a THz-spectroscopy system, a CO2 laser source as well as an infrared spectrometer are applied for. For the infrared spectroscopy, we will additionally require an infrared broadband source, which can be used from the room-temperature near-field microscope we are applying for in parallel. The funding possibility for this instrument has been granted in the framework of the basic funding for the call of Prof. Weitz to Göttingen, and is an essential tool for the building up of the group. With the microscope, we will be able to perform various highly innovative experiments in the area of modern solid-state research. For example, we will be able to perform unique investigations in the field of organic electronics. Specifically, we will firstly be able to locally visualize the temperature dependence of the THz conductivity of individual polymer fibers and low-molecular films with nm resolution. This will add significant understanding to the theory of charge-transport mechanisms. Additionally, we will use the unique capability of local infrared spectroscopy to detect the electrical degradation of organic semiconductors as function of temperature. With the as-established methods, we will additionally add basic understanding towards the conductivity of novel metalorganic frameworks. For the area of van-der-Waals materials the applied-for instrument will be additionally extremely important, as it will allow unique understanding of e.g. novel superconductive phases. To this end, we will use lateral mapping of the temperature dependent local conductivity in the infrared with a lateral resolution of below 10 nm to potentially firstly detect the appearance of local superconductive phases e.g in rhombohedral multilayer graphene. Additionally we will firstly be able to trace the temperature dependence of topologically protected states in bilayer graphene or in heterostructures composed of novel two-dimensional polymers and graphene. This unique instrument will additionally allow unique insights into the local appearance of phase transitions in strongly-correlated oxides and charge-density materials as function of temperature.