Student author: Natalie Ferris
Student author: Ruthie Strauss
Student author: Hongyi Li
American Journal of Physics
We discuss Young’s double-slit experiment using a partially coherent light source consisting of a helium-neon laser incident on a rotating piece of white paper. Such an experiment is appropriate for undergraduate students as an independent project or as part of an advanced lab course. As is well known, the resulting interference pattern is observed to disappear and return, depending on the angular size of the source. Interestingly, while the standard theoretical prediction for the light intensity agrees quite well with experimental data when the fringe visibility is high, the prediction is noticeably off when the visibility is low. A first-principles calculation of the light intensity is performed and shown to agree extremely well with the experimental results for all visibilities.
Jackson, David P., Natalie Ferris, Ruthie Strauss, Hongyi Li, and Brett J. Pearson. "Subtleties with Young's Double-Slit Experiment: Investigation of Spatial Coherence and Fringe Visibility." American Journal of Physics 86, no. 9 (2018): 683-689. https://aapt.scitation.org/doi/10.1119/1.5047438