Student Profile

Senior Project Profile: Albert Chien

Vibration Mitigation for Atomic-Resolution Imaging”

Albert Chien, S.B. ’19, mechanical engineering

Advisor: Jenny Hoffman, Professor of Physics and Applied Physics

Scanning tunneling microscopes (STM) in the Hoffman Lab can measure minuscule electronic features within a material, but they require extremely quiet environments. Even the tiny vibrations in a building can be problematic during such precise experiments. Chien developed a novel, post-processing method that records the vibrations during a measurement and then cancels vibration from the data after the experiment has been completed. His algorithm was able to reduce up to 80 percent of vibrations and allowed for accurate atomic resolution imaging in extremely noisy conditions. He tested the algorithm by placing a box fan on a microscope’s optical table. The algorithm could offer an effective way to reduce the effects of vibrations while keeping costs low, Chien said.

“The biggest challenge of the project was working with the native software which controls the microscope,” he said. “Due to the limited access to the microscope data, I had to develop several different approaches to either mimic or circumvent functions within the native microscope controller.”