Schawlow, Arthur L.

▪ 2000

      American physicist (b. May 5, 1921, Mount Vernon, N.Y.—d. April 28, 1999, Palo Alto, Calif.), shared the 1981 Nobel Prize for Physics with Nicolaas Bloembergen and Kai Manne Börje Siegbahn for work on laser spectroscopy. Originally interested in radio engineering, Schawlow won a scholarship to study mathematics and physics at the University of Toronto, where he earned a Ph.D. in 1949. On postdoctoral fellowship at Columbia University, New York City, he conducted research with physicist Charles H. Townes. Schawlow and Townes co-wrote Microwave Spectroscopy, which was published (1955) a year after Townes pioneered the maser (microwave amplification by stimulated emission of radiation). By the late 1950s their work to enhance the maser had yielded the optical maser, later known as the laser (light amplification by stimulated emission of radiation). Schawlow's flash of inspiration in laser design called for enhancing a light beam in a tube with mirrors at either end; because one of the mirrors was semitransparent, the beam passed through upon reaching a determined energy level. The first working laser was built in 1960 by Theodore H. Maiman, in part on the basis of their concepts. Schawlow then applied the laser to experiments in spectroscopy. As a professor (1961–91) at Stanford University, he was nicknamed Laser Man for his popular demonstrations, which included using a laser to burst a dark balloon inside a transparent balloon that remained undamaged. He scoffed at the popularization of lasers as “death rays” and took satisfaction in the fact that lasers became useful tools in many fields.

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▪ American physicist

in full  Arthur Leonard Schawlow 

born May 5, 1921, Mount Vernon, N.Y., U.S.

died April 28, 1999, Palo Alto, Calif.

 American physicist and corecipient, with Nicolaas Bloembergen (Bloembergen, Nicolaas) of the United States and Kai Manne Börje Siegbahn (Siegbahn, Kai Manne Börje) of Sweden, of the 1981 Nobel Prize for Physics for his work in developing the laser and in laser spectroscopy.

      As a child, Schawlow moved with his family to Canada. He attended the University of Toronto, receiving his Ph.D. in 1949. In that year he went to Columbia University, where he began collaborating with Charles Townes (Townes, Charles Hard) on the development of the maser (a device that produces and amplifies electromagnetic radiation mainly in the microwave region of the spectrum), the laser (a device similar to the maser that produces an intense beam of light of a single colour), and laser spectroscopy. Schawlow worked on the project that led to the construction of the first working maser in 1953 (for which Townes received a share of the 1964 Nobel Prize for Physics). 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 (Maiman, Theodore H.), 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. His works include Infrared and Optical Masers (1958) and Lasers and Their Uses (1983). A few years after winning the Nobel Prize, Schawlow wrote an article on the laser for Encyclopædia Britannica's 1987 Yearbook of Science and the Future. (See the Britannica Classic: .)

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