Arthur Schawlow and Charles Townes, “Infrared and Optical Masers” in Physical Review, American Physical Society, 112 No. 6 pp. 1940–1948, December 15, 1958. Original wrappers; there's a little damage to the spine; name stamped on front cover. VG $350
First proposal for the construction of a Laser (“Light Amplification by Stimulated Emission of Radiation”).
“It wasn’t until the 1940s and 1950s that physicists found a use for the concept [stimulated by Einstein in 1917], even though all that was required to invent a laser was finding the right kind of atom, and adding reflecting mirrors to fortify the stimulated emission process by producing a chain reaction. Charles Townes had worked on radar systems during World War II. After the war ended, he turned his attention to molecular spectroscopy, a technique that studies the absorption of light by molecules. Just like radar, molecular spectroscopy bombards the surface of molecules with light and analyzes the scattered radiation to determine the molecule’s structure. But the technique was limited by the wavelength of the light produced: in this case, the microwave regime of the electromagnetic spectrum. Townes noticed that as the wavelength of the microwaves shortened, the more strongly the light interacted with the molecules, and the more one could learn about them. He thought it might be possible to develop a device that produced light at much shorter wavelengths. The best way to do this, he thought, would be to use molecules to generate the desired frequencies through stimulated emission. Townes mentioned the idea to a colleague (later his brother-in-law), Arthur Schawlow, who proposed that the prototype laser be fitted with a pair of mirrors, one at each end of the lasing cavity. Photons of specific wavelengths would then reflect off the mirrors and travel back and forth through the lasing medium. By doing so, they would in turn cause other electrons to relax back into their ground states, emitting even more photons in the same wavelength. So only photons in the selected wavelength and frequency range would be amplified. The two men wrote a paper [this paper] detailing their concept, published in the December 1958 issue of the Physical Review, although they had yet to build a working prototype. They received a patent for their design two years later–the same year that the first working laser was built by Theodore Maiman at Hughes Aircraft Company.”--”Einstein Predicts Stimulated Emission”, August-September 2005 (vol 14 #8), APS This Month in Physics History.
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