Laser

Physical Review 112, 15 December 1958

The Physical Review published Arthur L. Schawlow and Charles H. Townes's paper "Infrared and Optical Masers" on 15 December 1958, in volume 112, issue 6, at pages 1940-1949. The journal records 26 August as the manuscript's receipt date.

The authors analyzed how maser techniques could be extended into the infrared and optical regions, including optical pumping and a resonant cavity with highly reflecting end walls.

They explained that restricting the cavity's angular aperture could select a single mode and produce extremely monochromatic, coherent light, and used potassium vapor to illustrate the proposed design.

Optical maser, not laser

The paper's device is an optical maser throughout. The word LASER — light amplification by stimulated emission of radiation — is associated with Gordon Gould's 1957 notebook, not with any renaming performed here.

Schawlow worked at Bell Telephone Laboratories; Townes's permanent position was at Columbia University, which the APS listed as his address, and he consulted for Bell Labs and took part in its patent application.

A blueprint, not a device

The paper reported no constructed laser and no experimental laser emission. What it supplied was a technically actionable design, and laboratories began trying to realize it.

Theodore H. Maiman demonstrated the first working laser, a ruby device at Hughes Research Laboratories, in 1960. Credit and patent priority were afterward contested among Schawlow, Townes, Gould, Robert Dicke, Soviet researchers and others.