Jinmeng Shi wins best student poster for smoother terahertz laser layers

Jinmeng Shi, a Master of Applied Science student in Electrical and Computer Engineering, was named best student poster presenter at the International Conference on Molecular Beam Epitaxy in Ann Arbor, Michigan, held July 12 to 16, 2026. Professors Dayan Ban and Zbig Wasilewski co-supervise her.

Her research targets terahertz quantum cascade lasers, which are built from many extremely thin semiconductor layers, so small flaws at the interfaces can hurt performance. She is testing whether growing the layers on a different crystal orientation of gallium arsenide gives smoother interfaces, and her experiments found conditions for more predictable silicon doping while keeping the surfaces very smooth.

Shi began in Materials and Nanosciences on a joint program with Beijing Jiaotong University: two years in Beijing, then the final two at Waterloo. She says her supervisors changed how she treats failed experiments: she now examines the evidence for causes and uses it to decide what to try next.