Teaching laser physics by experiments

Experimental activities in the undergraduate physics curriculum often suffer from a lack of connection with the courses they are designed to support. This paper describes a set of experiments in laser physics based on a commercially available HeNe gain tube with one internal and one external mirror. The experiments take students through several important topics including the spatial and temporal properties of laser radiation, a rate equation based model for the laser, and elements of the underlying spectroscopy. The experiments can be integrated into existing courses or provide the backbone of a complete course with close integration of theory and experiment.