Have students open the Stern Gerlach simulation on their computers.
Let the students explore the program for several minutes and play with some of the software's capabilities.
Pull the class back together and ask them what each object in the simulation represents.
Be sure to tell the students that the oven fires out random states; to prepare the samples in a state that we want to use for any experiment, the first Stern-Gerlach device in the setup must be used for the preparation. Without the first device we would not be able to select a beam consisting only of atoms deflected in either spin up or spin down when the inhomogeneous magnetic field is aligned along any particular axis.
Once a beam is 'prepared' with a certain spin, then we can use a second device to analyze the spin - hence the names 'state preparation device' and 'analyzer'.
If time permits, have students set up the situation shown in slide 12 and run the simulation to make sure they can run the simulation before starting the lab.