Analyzing a Spin-1/2 Interferometer
Highlights of the activity
- Students are placed into small groups and asked to find several probability results from a Spin-$\frac{1}{2}$ interferometer using the Spins software.
- Then, the small groups will use projection operators to determine the mathematical representations of the states exiting from the final Stern-Gerlach device. These quantum states will also be used to complete the theoretical probabilities on the activity worksheet.
Reasons to spend class time on the activity
At this point in the quantum mechanics course, students are still trying to grasp how making a measurement affects the quantum state of a particle as well as how this operation is represented mathematically. This activity gives students an opportunity to compare the experimental results of using a Spin-$\frac{1}{2}$ interferometer to the theoretical results predicted by use of projection operators. Filling out the theoretical section is also a good exercise in using projection operators in bra-ket notation.