UROP Proceedings 2022-23

School of Science Department of Physics 57 Department of Physics Development of Nanopositioning Stage and Electronics for High-Resolution Microscopy Applications Supervisor: JAECK, Berthold / PHYS Student: YU, Cheuk Yin / PHYS Course: UROP1000, Summer Progressive experimentation on functional quantum materials demands for enhancement of microscopy methods. In contemporary microscopic applications, scanning probe microscopy (SPM) is a conventional technique which maps the surface of specimens with a scanning tip. To obtain quality images, applying the usage of nanopositioning stages which are competent in specimen positioning down to nanometer-scale precision is one of the requisites. In parallel to our team’s preceding strategy in effectuating z-axis positioner, prototypes of x-axis and y-axis positioners, also featuring piezo-driven kinetics, have been progressed lately to cater to raster surveying on the x-y plane. This report summarizes the underlying conceptions in prototype design, outlines the course of configuring the positioners, together with presenting the interpretation regarding their performance. Development of a Transimpedance Amplifier for the Operation of a qPlus Atomic Force Microscope Supervisor: JAECK, Berthold / PHYS Student: FAN, Ka Cheuk / PHYS-IRE Course: UROP1100, Summer Advance scanning probe microscopy techniques have played an important role in the discovery of novel physical properties of materials. Atomic Force Microscopy techniques is one of the most powerful imaging and manipulating tool that applicable to wide range of pressure and temperature. Here, a Qplus AFM techniques combined with Microwave Impedance Microscopy (MIM) technique to study local conductivity and permittivity of materials. The Qplus AFM technique can control the tip-sample distance by the resonance of the Qplus sensor and piezoelectric effect. A small input alternating current signal from the sensor need to be amplified and converted to voltage signal to determine the tip-sample distance. Therefore, a home-made transimpedance amplifier circuit is designed and implemented for the operation of the Qplus AFM technique. Epitaxial Growth of Magnetic Kagome Metals Supervisor: JAECK, Berthold / PHYS Student: ZHENG, Ce / PHYS Course: UROP1000, Summer In this paper, we focus on the properties, preparation and characterisation of Kagome metal, a new type of metallic material, which is named after its honeycomb lattice structure. The lattice structure of Kagome metal has very specific electronic properties, and therefore exhibits a wide range of physical properties, which are The lattice structure of Kagome metal has very special electronic properties and therefore exhibits a wide range of physical properties. Generally speaking, there are many methods used to prepare and characterise Kagome metal. In this paper, we focus on the preparation of Kagome metal using the molecular epitaxial beam technique and use a PPMS device to investigate the material properties and to obtain relevant physical conclusions.