Laser
Charles Hard Townes and graduate students James P. Gordon and Herbert J. Zeiger produced the first microwave amplifier
Columbia University, New York, U.S.
In 1953, Charles Hard Townes and graduate students James P. Gordon and Herbert J. Zeiger produced the first microwave amplifier, a device operating on similar principles to the laser, but amplifying microwave radiation rather than infrared or visible radiation. Townes's maser was incapable of continuous output.