At the age of 16 he completed high school and received a scholarship in science at the University of Toronto. After earning his undergraduate degree Schawlow continued in graduate school at the University of Toronto which was interrupted due to World War II. At the end of the war he began work on his Ph.D at U of T with Professor Malcolm Crawford. He then took a postdoctoral position with Charles Townes at the physics department of Columbia University in the fall of 1949.
In 1951 he married Aurelia Townes, younger sister to Charles Townes, and together they had three children; Arthur Jr., Helen, and Edith. Arthur Jr. was autistic, with very little speech ability. He considered himself to be an orthodox Protestant Christian and attended a Methodist Church.
Schawlow and Professor Robert Hofstadter at Stanford, who also had an autistic child, teamed up to help each other find solutions to the condition. Arthur Jr. was put in a special center for autistic individuals, and later Schawlow put together an institution to care for people with autism in Paradise, California. It was later named the Arthur Schawlow Center in 1999, shortly before his death.
Schawlow was a promoter of the controversial method of facilitated communication with patients of autism.
Although his research focused on optics, in particular, lasers and their use in spectroscopy, he also pursued investigations in the areas of superconductivity and nuclear resonance. Schawlow shared the 1981 Nobel Prize in Physics with Nicolaas Bloembergen and Kai Siegbahn for their contributions to the development of laser spectroscopy.
In 1991 the NEC Corporation and the American Physical Society established a prize: the Arthur L. Schawlow Prize in Laser Science. The prize is awarded annually to "candidates who have made outstanding contributions to basic research using lasers."