📄️ Memristor effect in 2D materials
STM is a powerful characterization techinque providing imaging at atomic resolution as well as equally precise probing tool. STM is limited to reasonably flat and conducting samples, but fortunately this makes it an ideal tool to study most 2D materials.
📄️ Tip Induced Phase Changes
Similar to how STM can be used to create or erase defectsCITETHIS with the surface before and after visuallized with atomic resolution, I am investigating the use of the STM tip to trigger local phase changes on notable phase change material, In2Se3, with applied voltage pulses.
📄️ Layer-by-Layer Phase Changes
PCM devices offer strong scalability and low power consumption for the future of memory storage and computing. However, multistate operation is a key requirement for high density storage or operation in neuromorphic systems. Previous studies on In2Se3 based memory devices report a simple, two state (HRS, LRS) electrical configurationwhich has also been observed in other 2D materials. On the other hand, prelimnary transport measurensts with a 4-probe STM system reveleaed a much more interesting, multi-state switching behavior which covers six orders of magnitude range in device resistance.
📄️ Co Reconstruction by H Exposure
The interaction of hydrogen with cobalt metal is of much interest, as it frequently plays a large role in materials science, heterogeneous catalysis, electrochemistry, and energy storage. It is well understood that when a gaseous species adsorbs onto a solid surface, that surface will be altered. This alteration can be electronic, chemical, or physical, and the degree of alteration can be insignificant to substantial. In addition to hydrogen on the surface of a solid, the ability of hydrogen atoms to diffuse through surfaces makes the interaction of a solid with subsurface hydrogen of much importance. Surface as well as subsurface hydrogen can cause changes to the surface of a solid. For any given process, these changes to the surface can be beneficial or detrimental in a small or large way. Understanding the effect an adsorbate as well as subsurface species have on a surface is crucial for understanding and making improvements to important processes.