The Maser—New Type of Microwave Amplifier, Frequency Standard, and Spectrometer

  title={The Maser—New Type of Microwave Amplifier, Frequency Standard, and Spectrometer},
  author={James P. Gordon and Herbert J. Zeiger and Charles H. Townes},
  journal={Physical Review},
A type of device is described which can be used as a microwave amplifier, spectrometer, or oscillator. Experimental results are given. When operated as a spectrometer, the device has good sensitivity, and, by eliminating the usual Doppler broadening, a resolution of 7 kc/sec has been achieved. Operated as an oscillator, the device produced a frequency stable to at least 4 parts in ${10}^{12}$ in times of the order of a second, and stable over periods of an hour or more to at least a part in… Expand

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