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NBS and the Laser On the 50th Anniversary of the Laser

When the first laser was demonstrated fifty years ago, it was seen mostly as a solution in search of a problem. As lasers were further developed, NBS/NIST scientists were quick to put them to good use.

1974 Gold Medal awardees for work on frequency and wavelength standards. Standing L to R: Barger, Hall, Petersen, Wells. Seated L to R: Evenson, Danielson and Day. Photo courtesy: NIST
For example, used in conjunction with the cesium atomic clock (9.19GHz), the laser made possible the goal of defining the standard of length (meter) in terms of the standard of time (second)and a fixed (exact) value for the speed of light, a major metrological and historical accomplishment. This was accomplished from 1969 to 1983 in a collaboration between the NBS Laboratories in Boulder and Gaithersburg by measuring the frequency of the iodine stabilized HeNe laser (4.73THz) by direct frequency counting. Improved laser technology led to its use for Doppler-free precision spectroscopy, to the development of laser cooling and trapping, and to the demonstration of Bose-Einstein condensation. Howard Layer and Bill Phillips, two pioneers in this research, will review these accomplishments in their historical context.

Evenson and lasers. Photo courtesy: Howard Layer

Anyone outside NIST wishing to attend must be sponsored by a NIST employee and receive a visitor badge.

For more information, contact Kum Ham at 301-975-4203.

Colloquia are videotaped and available in the NIST Research Library.

Howard P. Layer and William D. Phillips
NBS/NIST Laser Pioneers

Created November 16, 2010, Updated January 5, 2017