Arthur Leonard Schawlow was an American physicist. He was born on May 5, 1921 in Mount Vernon, New York, United States. Schawlow received a B.A. degree from the University of Toronto in 1941. From 1941 to 1944, during World War II (1939-1945), he taught physics classes for military personnel at the university. He earned an M.A. degree in physics in 1942. After the war ended in 1945, Schawlow returned to his studies at the university and earned a Ph.D. degree in 1949. Schawlow was a research physicist at Bell Telephone Laboratories from 1951 to 1961. In 1958 he and Townes published a paper in which they outlined the working principles of the laser, though the first such working device was built by another American physicist, Theodore Maiman, in 1960. In 1961 Schawlow became a professor at Stanford University. He became a world authority on laser spectroscopy, and he and Bloembergen earned their share of the 1981 Nobel Prize by using lasers to study the interactions of electromagnetic radiation with matter. In 1991, he received the National Medal Of Science.Arthur Leonard Schawlow was an American physicist. He was born on May 5, 1921 in Mount Vernon, New York, United States. Schawlow received a B.A. degree from the University of Toronto in 1941. From 1941 to 1944, during World War II (1939-1945), he taught physics classes for military personnel at the university. He earned an M.A. degree in physics in 1942. After the war ended in 1945, Schawlow returned to his studies at the university and earned a Ph.D. degree in 1949. Schawlow was a research physicist at Bell Telephone Laboratories from 1951 to 1961. In 1958 he and Townes published a paper in which they outlined the working principles of the laser, though the first such working device was built by another American physicist, Theodore Maiman, in 1960. In 1961 Schawlow became a professor at Stanford University. He became a world authority on laser spectroscopy, and he and Bloembergen earned their share of the 1981 Nobel Prize by using lasers to study the interactions of electromagnetic radiation with matter. In 1991, he received the National Medal Of Science.