The first laser
Charles H. Townes
from A Century of Nature: Twenty-One Discoveries that Changed Science and the World
Laura Garwin and Tim Lincoln, editors
When the first working laser was reported in 1960, it was described as "a solution looking for a problem." But before long the laser's distinctive qualities—its ability to generate an intense, very narrow beam of light of a single wavelength—were being harnessed for science, technology and medicine. Today, lasers are everywhere: from research laboratories at the cutting edge of quantum physics to medical clinics, supermarket checkouts and the telephone network.
Theodore Maiman made the first laser operate on 16 May 1960 at the Hughes Research Laboratory in California, by shining a high-power flash lamp on a ruby rod with silver-coated surfaces. He promptly submitted a short report of the work to the journal Physical Review Letters, but the editors turned it down. Some have thought this was because the Physical Review had announced that it was receiving too many papers on masers—the longer-wavelength predecessors of the laser—and had announced that any further papers would be turned down. But Simon Pasternack, who was an editor of Physical Review Letters at the time, has said that he turned down this historic paper because Maiman had just published, in June 1960, an article on the excitation of ruby with light, with an examination of the relaxation times between quantum states, and that the new work seemed to be simply more of the same. Pasternack's reaction perhaps reflects the limited understanding at the time of the nature of lasers and their significance. Eager to get his work quickly into publication, Maiman then turned to Nature, usually even more selective than Physical Review Letters, where the paper was better received and published on 6 August.
With official publication of Maiman's first laser under way, the Hughes Research Laboratory made the first public announcement to the news media on 7 July 1960. This created quite a stir, with front-page newspaper discussions of possible death rays, but also some skepticism among scientists, who were not yet able to see the careful and logically complete Nature paper. Another source of doubt came from the fact that Maiman did not report having seen a bright beam of light, which was the expected characteristic of a laser. I myself asked several of the Hughes group whether they had seen a bright beam, which surprisingly they had not. Maiman's experiment was not set up to allow a simple beam to come out of it, but he analyzed the spectrum of light emitted and found a marked narrowing of the range of frequencies that it contained. This was just what had been predicted by the theoretical paper on optical masers (or lasers) by Art Schawlow and myself, and had been seen in the masers that produced the longer-wavelength microwave radiation. This evidence, presented in figure 2 of Maiman's Nature paper, was definite proof of laser action. Shortly afterward, both in Maiman's laboratory at Hughes and in Schawlow's at Bell Laboratories in New Jersey, bright red spots from ruby laser beams hitting the laboratory wall were seen and admired.
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