Honors Undergraduate Research Symposium Presentation
Author: Andrew Files | Major: Mechanical Engineering and Physics | Semester: Spring 2024
My name is Andrew Files, and I am majoring in Mechanical Engineering and Physics. I am a part of the College of Engineering, Fulbright College of Arts and Sciences and the Honors College. I am conducting research under Dr. Hiro Nakamura in the Department of Physics. This semester I worked under Dr. Nakamura in the Quantum Photonics lab on the project ‘Developing Titanium Oxide Platform for Quantum Photonics.’ This project spans multiple semesters, and I will continue to work on this project in the Fall Semester.
I was approached by my TA in my University Physics I lab about doing research under Dr. Nakamura in the Spring of 2023. I met with him, and we talked about what types of projects the Quantum Photonics lab works on and where I might fit into all of it. He decided that for the Fall Semester of 2023, it would be best if I continued the work on a previous project where another student had left off. I began developing and optimizing a system to view the generation of the Spontaneous Parametric Down-Converted (SPDC) photons in a non-linear Barium Borate (BBO) crystal. The original focus was just to develop that system, however, after receiving the Honors College Research Grant, I was able to expand the scope of my research to testing the versatility of titanium oxide in the field of quantum photonics.
Titanium oxide is an easy-to-manufacture material that is present in a large number of commercial products, including sunscreen, white pigments, and dielectric mirrors. It also has interesting structural properties when in crystal form. When doped with certain impurities, namely Thulium and Erbium, titanium oxide can form vacancies in its crystal lattice. These are similar to Nitrogen Vacancies (NV) in diamonds. These vacancies have properties that make them useful for quantum technologies. However, NV diamonds are more expensive and harder to create than titanium oxide crystals with similar vacancies. This project aims to explore whether titanium oxide doped with specific impurities can be used for these technologies.
This semester, I continued the work of developing the system to view the SPDC phenomenon with the focus on eventually transitioning to creating the titanium oxide crystals. However, after several setbacks I was only able to get through developing the imaging system. The main issues with the system were in the software that controlled the system and reliably creating the SPDC phenomenon.
The software issues revolved around two factors: a bug in the code that caused the scans to slow down exponentially the larger they were, and an issue in the communication between the sensor and the code processing the data. This meant that instead of focusing on generating the SPDC photons, I spent the first half of the semester fixing the issues in the code. Once these were fixed, I was able to work on SPDC, from there, my experimental setup went through three iterations. Each trying to isolate certain aspects of the phenomenon to find the right criteria for generation. This is where Dr. Nakamura stepped in as my faculty mentor. I am new to the field of nonlinear optics, and thus lack some of the understanding necessary to discern how to isolate these pieces. He gave me the information necessary to change my setup in a way that would search for different traces of SPDC generation. I also received guidance from several other students in the lab with more experience. The Quantum Photonics lab has several different projects happening simultaneously, so there was always someone willing to help.
I presented my methodology and preliminary data at the Honors Undergraduate Research Symposium this semester under the title ‘Developing a Single-Photon Image system based on a Scanning Avalanche Photo-Diode’. My future plans are to move on to creating the Titanium Oxide crystals and optimizing the imaging system to detect the impurity sites present in the crystals.