Maser

Device for producing coherent EM waves in the sub-visible spectrum

A maser is a device that produces coherent electromagnetic waves (microwaves) through amplification by stimulated emission. The term is an acronym for microwave amplification by stimulated emission of radiation. Nikolay Basov, Alexander Prokhorov and Joseph Weber introduced the concept of the maser in 1952, and Charles H. Townes, James P. Gordon, and Herbert J. Zeiger built the first maser at Columbia University in 1953.

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