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An Assessment of Four Divisions of the Physical Measurement Laboratory at the National Institute of Standards and Technology Fiscal Year 2018 (2018) / Chapter Skim
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5 Time and Frequency Division
Pages 33-39

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From page 33...
... ASSESSMENT OF TECHNICAL PROGRAMS Time and Frequency Services NIST disseminates time signals based on the coordinated universal time (UTC) time scale, the internationally generated scale that is coordinated by the International Bureau of Weights and Measures in France.
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From page 34...
... Optical Frequency Metrology and Ion Storage A New Generation of Frequency Standards A revolution in metrology is under way, enabled by the invention of the optical frequency comb and the development of trapped ion and atom lattice optical clocks. NIST's TFD is a leader in all of these developments.
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From page 35...
... , low-phase noise microwave generation, and precision optical frequency synthesis. In another alternative approach, TFD researchers have developed electro-optic combs (combs generated via strong-phase modulation of a single-frequency input laser)
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From page 36...
... Future experiments with longer distance fiber networks and free space time/frequency transfer are essential for taking advantage of the levels of precision being provided by the new generation of optical frequency standards. A final challenge to the redefinition of the second is gravity, which is a nuisance, an opportunity, and a dilemma.
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From page 37...
... This stimulated the military and telecommunications industry to develop a new class of small and relatively inexpensive metrological instruments that are described under the rubric of NIST-on-a-chip, a NIST-wide initiative to which the ADIG is a contributor and PML the lead. One class of the proposed chip instruments involves metrological tools based on accurate representations of SI base units such as length, electric current, temperature, luminous intensity, and, of course, time.
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From page 38...
... DISSEMINATION AND TECHNOLOGY TRANSFER At the top of TFD's agenda is the dissemination of time and frequency, an enormous responsibility that it meets at the highest level. However, the TFD provides many other services to the community: it performs 500 to 600 calibrations per year -- for example, precision phase-noise calibrations at a level unique in the world; it provides calibration equipment and specialized services directly to about 50 industrial firms, which greatly reduces calibration time for industry and reduces the calibration burden on the TFD; and it helps industry to develop new products such as the chip-scale atomic clocks, magnetometers, and phase noise test equipment.
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From page 39...
... The review did not include presentations of policies regarding mechanisms for fostering product development through spinning off companies, sponsoring Small Business Innovation Research grants, or policies such as employee leaves to pursue commercialization activities. It is worth making sure that clear policies governing such activities related to technology transfer are in place and communicated to staff.
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Key Terms

  • optical frequency
  • atomic clocks
  • frequency combs
  • frequency information
  • frequency comb

  • optical lattice
  • optical clocks
  • time signals
  • phase noise
  • electric current

  • tfd researchers
  • widely regarded
  • lattice frequency
  • frequency standard
  • frequency uncertainty

  • comparing frequency
  • frequency transfer
  • frequency metrology
  • nist time
  • optical frequencies

  • nist provides
  • time service
  • nist employs
  • transmitting time
  • independent ytterbium

  • time scale
  • trapped ion
  • ion storage
  • business innovation
  • atomic clock


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