Electronic measurement of the Boltzmann constant with a quantum-voltage-calibrated Johnson-noise thermometer

Samuel Benz, D. Rod White, JiFeng Qu, Horst Rogalla, Weston Tew

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23 Citations (Scopus)


Currently, the CODATA value of the Boltzmann constant is dominated by a single gas-based thermometry measurement with a relative standard uncertainty of 1.8×10−6 [P.J. Mohr, B.N. Taylor, D.B. Newell, CODATA recommended values of the fundamental physical constants: 2006, Rev. Mod. Phys. 80 (2008) 633–730]. This article describes an electronic approach to measuring the Boltzmann constant that compares Johnson noise from a resistor at the water triple point with a pseudo-random noise generated using quantized ac-voltage synthesis. Measurement of the ratio of the two power spectral densities links Boltzmann's constant to Planck's constant. Recent experiments and detailed uncertainty analysis indicate that Boltzmann's constant can presently be determined using Johnson noise with a relative standard uncertainty below 10×10−6, which would support both historic and new determinations.
Original languageEnglish
Pages (from-to)849-858
Number of pages10
JournalComptes rendus physique
Issue number9
Publication statusPublished - 2010


  • Temperature
  • Boltzmann constant
  • Josephson arrays
  • METIS-271420
  • IR-79825
  • Johnson noise
  • Noise thermometry

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