The Overlooked Step in Quantum Devices

Author: Lance Yarbrough | Majors: Mechanical Engineering and Physics | Semester: Spring 2023

Blurb:

My name is Lance Yarbrough, and I am in both the Engineering College and Fulbright College of Arts and Sciences. I’m a senior in Physics and Mechanical Engineering, and my mentor is Hugh Churchill from the Physics department. I am currently in my 3rd semester of research with Dr. Churchill, and I am planning to continue research for the next 2 semesters before graduate school.

 

Research Details:

My research is directly related to the mechanical exfoliation of 2D materials, which are used in quantum computing and q-dots. My specific research, however, is focused on the exfoliation process for graphene, which is used to create thin-layer crystals for production of quantum computing. I am studying the factors that affect the quality of flakes, such as temperature, material properties of tape, and peeling force. I will suggest optimal flake exfoliation processes and apply them to the MonArk Quantum Foundry pipeline in my mentor’s lab.

I found my mentor, Dr. Churchill, through multiple Physics courses I had with him. I took University Physics 2 and Modern Physics with Dr. Churchill and took an interest in his passion for physics and how my learnings in class directly applied to his research. As a double major, I wanted to find a project that fell in between Mechanical Engineering and Physics. The mechanical exfoliation process was a natural fit because dynamics and material science from engineering is studied, but modern physics and experimental processes from physics are also looked at in depth.

This semester, in my research, I learned skills in COMSOL Multiphysics software, and how the Engineering process often relies on repeated simulations to work on optimization. In addition to this, I learned about the ideation process of developing tight tolerance machines, and the manufacturing process used to create these machines. I gained knowledge about adhesive material properties, and how to shift my focus as different information impacted my research. Before this semester, I was planning to look at the peel angle of tape, and how that affected the flake-size. However, through microscopic videography, I learned that the tape peel is similar to crack growth in ductile materials. Because of this, I had to shift my project’s focus, and it required me to work with my mentors to communicate my findings to help explain why my research needed shifting. In addition to this, however, I was able to understand the lack of microscopic documentation of mechanical exfoliation and use my knowledge to find a new area of exfoliation to target.

Through the help of Dr. Churchill and Josh Goss who work in the MonArk lab, and Dr. Wejinya who does research in nanomaterials for the Engineering department, I was able to develop a plan to simulate many tape pulls and verify my results through a tight-tolerance machine. Dr. Wejinya taught me about the importance of simulations and helped me start modelling the mechanical exfoliation of graphene. Then, with Dr. Churchill, I worked to understand the implications of microscopic documentation of mechanical exfoliation, and the lack of that in the academic community. Lastly, Josh Goss and I worked to develop a mechanism to record the mechanical exfoliation of graphene through microscopic videography.

Through the summer and the following semester, I am planning to finish building my videography mechanism, and begin formal simulations of mechanical exfoliation. Afterwards, I am planning to write a paper with hopes of being published in a scientific journal. Due to the lack of formal study of the mechanical exfoliation process, there is great potential for me to get published and travel to a nanomaterials conference to discuss my findings. I am planning to finish this portion of the research in the upcoming semester, so afterwards I can contribute directly to the MonArk quantum foundry and integrate my work to the quantum pipeline actively being developed. I am grateful for the Honors College Grant I received because it allows me to have funding to manufacture various mechanisms to aid my research process, but also to allow me to run cost-intensive simulations in order to simplify my research significantly.