Design Of A Sample Holder For In-situ Lorentz Transmission Electron Microscope And Related Magnetic Properties Investigation

With the improvement of the integration of devices in the traditional semiconductor industry,Moore's law is gradually becoming ineffective.Magnetoelectronics,which is based on the manipulation of new magnetic nanostructures,has become a hot research topic in recent years.New magnetic nanostructures,such as magnetic Skyrmions,magnetic Bobbers,and magnetic Bubbles have the advantages of small size,high stability and strong controllability.They are expected to bring new ideas for the development of information storage and processing devices with smaller size,lower energy consumption and higher storage density.From the perspective of fundamental research,grasping the physical properties of the new magnetic structures under the external of control magnetic field,electric field and current is the premise for the realization for realizing quantum functional devices.In this work,the dynamic behavior of a new three-dimensional magnetic structure magnetic Toron under current control is studied by using the method of micromagnetic simulations.Then,two in-situ transmission electron microscope sample holders equiped with in-situ transport testing system was designed.Moreover,the thermal steady-state simulation,physical processing,and experimental test are completed.One is the in-situ sample holder based on the Japanese electron transmission electron microscope to solve the problems of vacuum adiabatic and low-temperature conduction of the sample holder,and another is the in-situ sample holder based on the FEI Lorentz transmission electron microscope.The main innovative achievements are as follows:(1)The current regulation of a new magnetic structure,magnetic Toron,is studied in this work,the unidirectional motion of magnetic Toron in Fe Ge cylindrical nanowire driven by current is studied by means of micromagnetic simulation,and the origin mechanism of the unidirectional motion is analyzed.(2)The low-temperature sample holder was designed based on Japanese electron transmission electron microscope.The problems of vacuum adiabatic and low-temperature conduction of the sample holder were solved from four aspects: model design,thermal steady-state simulation,physical processing and experimental testing.(3)Based on FEI Lorentz transmission electron microscope,the in-situ sample holder was developed.And the design of the sample stage was completed in accordance with the in-situ experiment.The design requirements of cooling the sample position to a minimum temperature of 100 K and achieving high resolution and stable imaging of 0.4 nm in the transmission electron microscope were realized.Finally,the in-situ sample holder designed in this work was successfully developed,which can meet the experimental requirements of in-situ sample holder based on the in-situ transport system of Lorentz transmission electron microscope.