The Stern-Gerlach experiment is a fundamental experiment in quantum mechanics that demonstrates the quantization of angular momentum and the existence of quantum spin. It was first conducted by Otto Stern and Walther Gerlach in 1922. ### Setup: The experiment involves the following components: 1. **Beam of Silver Atoms**: A narrow beam of neutral silver atoms is used. Silver atoms have a single unpaired electron in their outer shell, leading to a net spin and magnetic moment.
Articles by others on the same topic
A Stern-Gerlach experiment separates atomic beams according to a component of their magnetic moment in a nonuniform magnetic field. For an appropriate two-state spin system, calibrated outputs distinguish the two spin eigenvalues; Stern-Gerlach expectation estimation explains how repeated fresh preparations turn channel counts into an expectation value.
The decisive contrast is between two separated components of an atomic beam and the continuous spread predicted for randomly oriented classical magnetic moments. Neither component need be an infinitely narrow spot: velocity spread and the resolving power of the scientific instrument affect the spatial image. The apparatus converts an internal magnetic moment into a displacement large enough to inspect, connecting angular momentum eigenstates to macroscopic evidence.
Originally done with (neutral) silver atoms in 1921, but even clearer theoretically was the hydrogen reproduction in 1927 by T. E. Phipps and J. B. Taylor.
The hydrogen experiment was apparently harder to do and the result is less visible, TODO why: physics.stackexchange.com/questions/33021/why-silver-atoms-were-used-in-stern-gerlach-experiment
The Stern-Gerlach Experiment by Educational Services, Inc (1967)
Source. Featuring MIT Professor Jerrold R. Zacharias. Amazing experimental setup demonstration, he takes apart much of the experiment to show what's going on.