The Mach–Zehnder interferometer has played an important role both in quantum and classical physics
research over the years. In physics education, it has been used as a didactic tool for quantum
physics teaching, allowing fundamental concepts, such as particle–wave duality, to be addressed from
the very beginning. For a student to understand the novelties of the quantum scenario, it is first
worth introducing the classical picture. In this paper, we introduce a new version of the software
developed by our research group to deepen the discussion on the classical picture of the
Mach–Zehnder interferometer. We present its equivalence with the double slit experiment and we
derive the mathematical expressions relating to the interference pattern. We also explore the
concept of visibility (which is very important for understanding wave–particle complementarity in
quantum physics) to help students become familiar with this experiment and to enhance their
knowledge of its counterintuitiv…