In a small lab on the second floor of the Natural Science Center, students in the Department of Physics and Astronomy use a combination of optical tweezers and microscopes to study colloidal particles, tiny particles held in water. We are working on a unique project. A laser is used to hold and capture the particles.
Fiona Lorenzen, a sophomore applied physics major, and José Rojas, a junior mathematics/physics major, are students currently working on an ongoing project under the supervision of Jerome Huang, associate professor in the Department of Physics and Astronomy. is. The process begins by diluting the particles, primarily silica, so that they can be seen better under a microscope. The particles are then identified, captured, and examined using optical tweezers.
According to Britannica, silica is one of the main components of glass and also makes up 59% of the Earth’s crust. Rojas and senior Yash Mohod developed a computer program in the summer of 2024 that controls a camera that captures the seemingly random movement of particles. The camera is connected to a microscope and computer monitor, which Hung said was necessary for safety.
“It’s not safe to put your eyes downstream (of the microscope) because of the lasers being used,” Huang said.
Huang said the goal is to learn more about glass by studying the behavior of silica particles and why it behaves like a solid despite its liquid composition. He said the project has been underway since 2019 after the ministry purchased a large optical table to conduct experiments. Since then, students from other classes have joined the project and worked on integrating new components, including code development.
Rojas said he embarked on the project after talking with his physics advisor, Huang, over the summer.
“He told me stories about coding and microscopy that I was really interested in,” Rojas said. “And I said, ‘Yeah, why not?’
Rojas said the code, which he first started working on in the summer of 2024, will help different components such as cameras and spatial light modulators work together at the same time. A spatial light modulator controls the microscope’s position, Huang said in an email. Rojas said that although he learned some coding basics in his college classes, it was still difficult to understand and learn how to operate all the equipment.
“But I think that’s why I liked[the project]because I was starting to understand everything a little bit,” Rojas said.
Lorenzen said he became involved because he was interested in the chemistry and coding aspects of the research.
“When I saw this setup, I thought, ‘Wow, that’s interesting,’ even though it was quite complicated,” says Lorenzen.
Lorenzen said the small size of the department allowed him to gain hands-on experience. The department has 10 faculty members and 36 students and offers three undergraduate majors: Physics, Applied Physics, and Mathematical Physics. She said this allowed her to quickly build relationships with colleagues and professors, making it easier to collaborate.
“It gave me far more opportunities than I would have at a large state school,” she said. “You get closer to your professors and it feels like a closer-knit community.”
Mr. Huang has helped organize events in the Physics and Astronomy Department, such as “Retro Rewind Day,” which provides an opportunity for students and professors to interact by playing retro video games together.
Another aspect of the department that Huang is involved with is the anti-racism and inclusion plan developed by faculty members in December 2020. Huang said women and racial minorities are underrepresented in the field of physics.
“We decided as a department that we wanted to do whatever we could about this issue,” Huang said.
The plan says the department will invite female physicists to speak at seminars and overhaul its faculty hiring procedures to include a more diverse range of experts.
Regarding issues with inclusivity that the department experiences, Fung said not all students have a basic knowledge of the subjects taught in introductory high school physics classes. This left some students feeling overwhelmed and others feeling like they weren’t learning much new material, he said.
“When you have the opportunity to take quality courses in high school, a lot of them are just a review, but for someone who has never seen something like that before, it can all be overwhelming,” Huang said. said. “Personally, I see this kind of chasm opening up between students in a way that I don’t think is healthy.”
Fan, along with other faculty in the department, has revised the curriculum to give students a more equal starting point, and while the topics are new, they provide students with the foundational mathematics needed for physics work. He said it also helped him develop his skills. Huang said in an email that even the optical tweezers project is accessible to those new to physics because it includes elements taught in introductory classes.
Lorenzen said that although it incorporates elements learned in class, she doesn’t necessarily see the project as a school project and enjoys the relaxed atmosphere.
“I think of a unit of research as a fun little break in the day,” Lorenzen said. “I think this is a really fun side adventure.”
But Lorenzen said she also appreciates the opportunity to gain real-world research experience.
“I get to do this amazing research that prepares me for real-world research and exposes me to a lot of new concepts,” Lorenzen said.
